please help

see attached picture​

Please Helpsee Attached Picture

Answers

Answer 1

Answer:

See Explanation

Step-by-step explanation:

For cement block:

Given is a square cement block, thus, it's width and height would be equal.

-> length (l)= h, width (w)= 2x, height (h) = 2x

[tex]V_{cement \: block} = lwh[/tex]

[tex]\implies V_{cement \: block} = h(2x)(2x)[/tex]

[tex]\implies V_{cement \: block} = 4x^2h.....(1)[/tex]

For cylinder:

Radius (r) = 2x/2 = x, height (h) = h

[tex]V_{cylinder} = \pi r^2 h[/tex]

[tex]\implies V_{cylinder} = \pi x^2 h.....(2)[/tex]

Subtract (2) from (1), we find:

[tex]V_{cement \: block}-V_{cylinder} = 4x^2h- \pi x^2 h[/tex]

[tex] V(cement \: block\: without\: cylinder)= x^2h(4- \pi)[/tex]

Thus proved

To solve 6.2.1 and 6.2.2 plug the given values in [tex]x^2h(4- \pi)[/tex] and calculate.

Related Questions

Which two numbers on the number line have an absolute value of 2.75?

Select the location of both numbers on the number line.

Answers

Two numbers on the number line have an absolute value of 2.75 is -2.75 and 2.75

number line - A line on which numbers are marked at intervals and used to illustrate simple numerical operations.

center of the number line is called origin i.e. 0 (zero) positive numbers are on the right side of zero. negative numbers are on the left side of the zero.

absolute value - absolute value of real number is its distance from the zero.

The absolute value of 2.75 is 2.75 and the absolute value of -2.75 is 2.75

Two numbers on the number line have an absolute value of 2.75 is -2.75 and 2.75

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kat is painting the edge of a triangular stage prop with reflective orange paint. the lengths of the edges of the triangle are (3x – 4) feet, (x2 – 1) feet, and (2x2 – 15) feet. what is the perimeter of the triangle if x

Answers

The perimeter of the triangle is 40 feet .

Kat is painting the edge of a triangular stage prop with reflective orange paint. the lengths of the edges of the triangle are (3x – 4) feet, (x2 – 1) feet, and (2x2 – 15) and x = 4

Now , According to the question:

Let the sides of triangle be a , b , c

a = 3x -4

b = x^2 -1

c = 2x^2 - 15

x = 4

Substitute the value of x in a, b , c

a = 3 × 4 -4 = 8 feet

b = 4 × 4 -1 = 15 feet

c = 2× 4× 4 - 15 = 17 feet

The perimeter of the triangle is sum of all sides

then, a + b + c

= 17 + 15 + 8 = 40 feet

Hence, The perimeter of the triangle is 40 feet .

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Joyce buys a bus pass for the month of March for $32.55. How much does the bus pass cost per day?

Answers

Answer: $1.05

Step-by-step explanation:

March has 31 days

Hence,

[tex]\displaystyle\\32.55:31=\\\\32\frac{55}{100}*\frac{1}{31} =\\\\32\frac{11}{20} *\frac{1}{31} =\\\\\frac{(32)(20)+11}{(20)(31)} =\\\\\frac{640+11}{620} =\\\\\frac{651}{620}=[/tex]

$1.05

-6/25 divided by 5 2/5 answer has to be a fraction and needed in simplest form

Answers

Answer:

-2/45

Step-by-step explanation:

-2/45 or 1/45 because I divided by 2 tell me if this makes sense English isn’t my first language

HELP!!
what is the answer to number 18

Answers

Answer:

c

Step-by-step explanation:

The number of solutions of the equation [tex]5x^2+7x-4=0[/tex] is 2. Option (c) is correct.

Further explanation:

The Fundamental Theorem of Algebra states that the polynomial has n roots if the degree of the polynomial is n.

The polynomial function has n roots or zeroes.

Given:

The equation is [tex]f(x)=5x^2-7x-4=0[/tex]

According to the Fundamental Theorem of Algebra the function has 2 roots

Solve the above equation to obtain the zeros.

[tex]x=\frac{-b\pm \sqrt{b^2-4ac}}{2a}[/tex]

[tex]x=\frac{-7\pm \sqrt{7^2-4\cdot \:5\left(-4\right)}}{2\cdot \:5}[/tex]

[tex]\sqrt{7^2-4\cdot \:5\left(-4\right)}[/tex]

[tex]=\sqrt{129}[/tex]

[tex]x_1=\frac{-7+\sqrt{129}}{2\cdot \:5},\:x_2=\frac{-7-\sqrt{129}}{2\cdot \:5}[/tex]

so, x has 2 solutions

Answer:

options c

Step-by-step explanation:

I hope it's helpful for you to

i have two 20-sided dice that each have 4 maroon sides, 7 teal sides, 8 cyan sides, and one sparkly side. if i roll both dice, what is the probability they come up the same?

Answers

The probability of color coming up the same for rolling two 20-sided dice is 129/400.

Probability is defined as how likely something is to happen. For a single dice, getting a maroon, teal, and cyan have a probability of 4/20, 7/20, and 8/20, respectively.

Before solving the probability, we must identify whether the events are considered independent or dependent. Independent events are when the probability of an event happening does not affect the other's event probability of happening. A dependent event is when the probability of an event happening affects the other event. The rolling of dice is considered an independent event.  

For events that should occur together, the multiplication rule is used. To solve for the probability of two sides coming up the same, the formula below is used.

P (A and B) = P (A) * P (B)

P (red and red) = (4/20)*(4/20) = 1/25

P (teal and teal) = (7/20)*(7/20) = 49/400

P (cyan and cyan) = (8/20)*(8/20) = 4/25

Since no specific color was stated in the problem, the sum of the probability of each color coming up the same is determined.

P (color come up the same) = P (red and red) + P (teal and teal) + P (cyan and cyan)

P (color come up the same) = 1/25 + 49/400 + 4/25

P (color come up the same) = 129/400

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What is the midpoint of PQ​

Answers

Answer:
Midpoint = (-0.5, 1)

Step-by-step explanation:

Midpoint formula is (x1 + x2)/2, (y1 + y2)

Lets plug that into the formula.

-4 + 3 = -1

x = -1/2 or -0.5


-1 + 3 = 2

2/2 = 1

y = 1

Final Answer: (-0.5, 1) or (-1/2, 1)

Shandra is working two summer jobs, making $9 per hour washing cars and $8 per hour walking dogs. Last week Shandra worked a total of 11 hours and earned a total of $90. Write a system of equations that could be used to determine the number of hours Shandra worked washing cars last week and the number of hours she worked walking dogs last week. Define the variables that you use to write the system. Let Let ||| System of Equations:​​

Answers

Step-by-step explanation:

x=total hours for wahing cars

y=total hours for walking dogs

1. 9x+8y=90 (total money)

2. x+y=11 (total hours)

=>8x+8y=88

=> 1-2

=> x=2

therefore y=9

The number of hours for Shandra working to wash car is 2 hours.

The number of hours for Shandra working to walking dogs is 9 hours.

What is an expression?

Mathematical expression is defined as the collection of the numbers variables and functions by using operations like addition, subtraction, multiplication, and division.

Given that;

Shandra is working two summer jobs, making $9 per hour washing cars and $8 per hour walking dogs.

Last week Shandra worked a total of 11 hours.

Total earned = $90

Now,

Total number of hours to wash car = x

Total number of hours to walk dogs = y

So, We can formulate;

⇒ 9x + 8y = $90  ... (I)

And, x + y = 11   .. (ii)

Solve equation (i) and (ii) we get;

x = 2 hours and y = 9 hours

So, The number of hours for Shandra working to wash car is 2 hours.

The number of hours for Shandra working to walking dogs is 9 hours.

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Evaluate 1+(-2/3)-(-m) where m =9/2

Answers

Answer:

Step-by-step explanation:

1+(-2/3)-(-9/2)\

1-2/3+9/2

29/6

Water Lillies (continued)
A nearby lake also has water lilies. The ranger uses the equation = 90 · 2 to represent the number of water lilies in the lake each day.
4. Explain what the 90 and the 2 mean in this situation.
5. If both patterns continue, which will have more water lilies on day 6: the pond or the lake?
Explain your reasoning.

Answers

Answer:

Step-by-step explanation:

5/3 in decimal form
Algebra 1 question

Answers

Answer:

1.66...

Step-by-step explanation:

5/3=

5 * 1/3=

5 * 0.33...=1.66...   ==> with bar on top of the 6

Simplify the following numerical expressions. |-7| - 7 = 2|-7| = (-7)2 = -72 = -7 -|-7| =

Answers

the answer of all the 5 expressions is given as : 0, 14, 49, -49, -14 respectively.

What is mathematic expression?

A mathematical expression is defined as the collection of the numbers variables and functions by using signs like addition, subtraction, multiplication, and division.

Here the given expression are :

1)  |-7| - 7 :

now, here considering the modulus value of -7 as 7 that is positive only :

 |-7| - 7 = 7-7 = 0

2) 2|-7| = 2x 7

   2|-7| = 14

3) (-7)² = -7 x -7 = 49

4) -7² = -(7 x 7) = -49

5) -7 -|-7| = -7 - 7 = -14

it should be noted that we have considered only positive value of modulus function only.

Therefore, the answer of all the 5 expressions is given above.

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Find the slope of the line that passes through the given points.

(-4,3) and (9,-2)

m=

Answers

Answer:

m=-5/13

Step-by-step explanation:

(-4,3) and (9,-2)

y2-y1/x2-x1

-2-3/9+4

-5/13

Hope this helps!

Please mark as brainliest if correct!

orthogonality on a circle suppose that ab is the diameter of a circle with center o and that c is a point on one of the two arcs joining a and b. show that ca⇀ and cb⇀ are orthogonal.

Answers

It is proved that ca⇀ and cb⇀ are orthogonal .

Let AO = - u vector , OB = u vector and OC = α vector .

According to question ,

u * u = v * v = r ^ 2 and

AC vector = AO vector + OC vector = u + v

BC vector = BO vector + OC vector v - u ,

Applying dot - product ,

( AC vector ) . ( BC vector ) = ( v + u ) . ( v - u )

                                            = ( v . v ) - ( u . u )

                                          = ( r ^ 2 ) - ( r ^ 2 )

                                           = 0

Hence , AC and BC are orthogonal .

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6. James and his

friend both started

a part-time job at

the Swimming Hole

earning $8.50 per

hour. James



worked 10 1/2

hours



his first week.

James agreed to

pay his friend $8.25

of his salary for

reimbursement of

gas. How much

money will James

have left after he

pays his friend for

gas?

Answers

The amount that James left has left after paying his friend 10% is; $80.325

How to Solve Algebra Word Problems?

We are told that James and his friend both earn $8.5 per hour. Thus;

Amount earned by James per hour = $8.5

Amount earned by the friend per hour = $8.5

Total time James works in his first week = 10 ¹/₂ hours

Now, James agreed to pay his friend 1/10 of his salary

Thus, amount that James earned is;

10.5 * 8.5 = $89.25

Thus, amount he has left after paying his friend 10% is;

(100% - 10%) * $89.25 = $80.325

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Calculate the value of y when the graph of y=-3x and x=-2 intercept

Answers

In a linear equation value of x and y  (x, y) = ( -2 , 6) when the graph of y=-3x and x=-2 intercept .

What in mathematics is a linear equation?

There are only one or two variables in a linear equation. No variable can be multiplied by a number larger than one or used as the denominator of a fraction in a linear equation. All of the points fall on the same line when you identify the values that together make a linear equation true and plot those values on a coordinate grid.

y= - 3x

Put x = -2 put in the equation

y = -3  * -2

y = 6

So, value of x and y  (x,y) = ( -2 , 6)

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3y=-12x + 6
y=-4x + 2

no solution
1 solution
or
infinitely many solutions

Answers

The given equation 3y = -12x + 6 has infinitely many solutions.

The given equation 3y = -12x + 6 can be solved using the substitution method to determine whether this equation has no solution, 1 solution or infinitely many solutions.

Given equation,

3y = -12x + 6

Rearranging the terms of the equation, we get the value of y in terms of the variable x.

=> 3y = -12x + 6

=> y = -12x/3 + 6/3

=> y = -4x + 2

Next, we substitute this value of y in terms of the variable x in the original equation,

=> 3 ( -4x + 2 ) = -12x + 6

=> -12x + 6 = -12x + 6

=> -12x + 12x = 6 - 6

=> 0 = 0

From the obtained result, we can conclude that this system has infinitely many solutions. This implies, the lines are coincident and the system is consistent and dependent.

Therefore, it can be concluded that the given equation 3y = -12x + 6 has infinitely many solutions.

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Match each group of numbers with the appropriate group name.
13, 0.781781...
a.
b.,1.5, -56.25
c. √5, 1.1,
d. 0.-€,0.975
e. √9,-4,892
[Choose]
Whole Numbers
Positive Numbers
Repeating Decimals
Improper Fractions
Numbers Between -1 and 1
Repeating Decimals
27

Answers

Answer:

A . 6822 just divede 420 to 32 then times 562 tk 911

Find the volume of the figure

Answers

Answer: 5 m³

Step-by-step explanation:

    We will break the figure into two different parts.

    Volume of a rectangular prism can be found with V = L * W * H

V = L * W * H

V = (2 m) * (1.5 m) * (1.5 m)

V = 4.5 m³

-

V = L * W * H

V = (2 m) * (2 m - 1.5 m) * (0.5 m)

V = 0.5 m³

    Now, we will add them together.

4.5 m³ + 0.5 m³ = 5 m³

Answer:

5m³

Step-by-step explanation:

Hello!

You can picture this rectangular prism as a whole prism with a part removed.

The dimensions of the whole prism are 1.5m, 2m, and 2m.

The part cut out is 1m, 0.5m, and 2m.

We can find the volume of the whole rectangular prism and subtract the volume of the removed part.

Find the volume(1.5 * 2 * 2) - (1 * 0.5 * 2)6 - 15

Since the units of length are meters, the volume should be represented as meters³. The volume is 5m³.

26 Mr Hussain buys 13 kg of onions, 3½ kg of potatoes and
7 kg of cabbage. What total mass does he carry home?

Answers

Answer:

23.5kg

Step-by-step explanation:

the total mass of the things he bought is what we are asked to find.

13kg of onions+3.5kg of potatoes+7kg of cabbage is the total mass he carried home.

=23.5kg

kirk made a scale drawing of the elementary school. the scale of the drawing was 3 millimeters : 4 meters. if the actual width of the schoolyard is 60 meters, how wide is the schoolyard in the drawing?

Answers

The width of the schoolyard in the drawing is 45 millimeter.

In the given statement is ,

kirk made a scale drawing of the elementary school. the scale of the drawing was 3 millimeters : 4 meters. if the actual width of the schoolyard is 60 meters.

To find the how wide is the schoolyard in the drawing

Now, According to the question:

and, Based on the given condition

Let width of the schoolyard in the drawing be x

So, 3 : 4 = x : 60

[If b/a = d/c, ad = bc]  

3/4 = x/60

3 x 60 = 4x

x = 180/4

x = 45 millimeters

Hence, The width of the schoolyard in the drawing is 45 millimeter.

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The length of a bacterial cell is about 5 x 10−6 m, and the length of an amoeba cell is about 3.5 x 10−4 m. How many times smaller is the bacterial cell than the amoeba cell? Write the final answer in scientific notation with the correct number of significant digits.

1.4 x 101
7 x 101
143 x 101
7 x 103

Answers

Bacterial cell is smaller than the amoeba cell by 70 times or 7^ 10 times

What is mathematical expression?

A mathematical expression is defined as the collection of the numbers variables and functions by using signs like addition, subtraction, multiplication, and division.

length of a bacterial cell = 5 x 10^-6 m

length of an amoeba cell = 3.5 x 10^-4 m

= 3.5 x 10^-4 x 100/100 m

= 350 x 10^-6 m

Now, comparing the length

= (350 x 10∧-6) / (5 x 10∧-6 )

= (350/5

= 70 times or 7^ 10 times

Therefore, bacterial cell is smaller than the amoeba cell by 70 times or 7^ 10 times

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what will the coordinates of the image be if point a (5;4) is reflected along the y-axis​

Answers

Answer:

(-5,4)

Step-by-step explanation:

when the coordinate is reflection it stays the same number but is change to  the opposite (-/+)

reflecting over the y-axis flip the X coordinate (-5,4)

reflecting over the x-axis flip the Y coordinate (5,-4)

HELP MEEE PLEASEEEEEEEE

Answers

Answer:

the answer is blank, don't type anything in just f a I l

Choose a mental math strategy, and find the difference between the speeds of the planets Neptune and Saturn

Answers

The difference between the speeds of the planets Neptune and Saturn is 9384 miles per hour.

What is speed?

The distance traveled in a unit of time is called speed. It refers to a thing's rate of movement. The scalar quantity known as speed is the velocity vector's magnitude. It has no clear direction. The formula for an object's general speed is [Speed = Distance Time]. M/s is the SI unit of speed.

The speed of an item, which is a scalar quantity in everyday usage and kinematics, is the size of the change in that object's position over time or the size of the change in that object's position per unit of time.

Therefore, the difference between the speeds of the planets Neptune and Saturn will be:

= 21637 - 12253

= 9384 miles per hour.

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Given that (-7, 2) is a point on a circle centered at (0, 2), which equation represents the circle?

Answers

If (-7,2) is a point on a circle centered at (0,2), the equation represents the circle is [tex]x^{2} +(y-2)^{2}=49[/tex]

Given,

Center of the circle = (0,2)

One point on the circle = (-7,2)

First we have to find the distance between the center and the given point

that is the radius of the circle.

[tex]d=\sqrt{(x_{2}-x_{1})^{2}+(y_{2}-y_{1})^{2} } \\d=\sqrt{(0+7)^{2}+(2-2)^{2} } \\d=\sqrt{49}[/tex]

d= 7  units

The standard equation of  the circle

[tex](x-h)^{2}+(y-k)^{2}=r^{2}[/tex]

Substitute the values in the equation

[tex](x-0)^{2}+(y-2)^{2}=7^{2} \\x^{2} +(y-2)^{2}=49[/tex]

Hence, If (-7,2) is a point on a circle centered at (0,2), the equation represents the circle is [tex]x^{2} +(y-2)^{2}=49[/tex]

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Answer:

Step-by-step explanation:

combine these radicals

Answers

Answer:

[tex]2 \sqrt{3} [/tex]

the tunnel opening shown is a semicircle. find the area to the nearest tenth, of the opening tunnel enclosed by the semi circle. (semi circle is 23 feet.)

Answers

A semicircle is a one-dimensional locus of points that forms half of a circle.

The area of the semicircle is 10796.9 square feet.

What is a semicircle?

A semicircle is a one-dimensional locus of points that forms half of a circle.

Its area is half the area of a circle.

We have,

The radius of the semicircle is 23 feet.

The figure is given below.

The area of a semicircle is given by:

= πr² / 2

r = radius

π = 22/7 = 3.14

So,

The area of the semicircle tunnel:

= (3.14 x 23 x 23) / 2

= 10796.89

Rounding to the nearest tenth.

= 10796.9 square feet

Thus the area of the semicircle is 10796.9 square feet.

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I need help on number 4

Answers

Answers:  Bimodal and Symmetric

Reason:

There are two mountain peaks, which show the two modes (at 0.27 and 0.31). Therefore, this data set is bimodal.

The data set is also symmetric because of the mirror line at 0.29; stuff to the left of 0.29 can be reflected over the mirror line to get the stuff on the right side.

We can rule out choice A since the curve doesn't represent a normal distribution. A normal distribution has exactly one mode only.

Choice C is ruled out because a skewed distribution isn't symmetric, and vice versa.

The data set isn't uniform since all stacks of points aren't the same height. This rules out choice E.

The two triangles below are similar.
Calculate the value of x.
Give your answer as an integer or as a fraction in its simplest form
15 mm
C
3 mm
xmm
D
10 mm
Not drawn accurately

Answers

Answer:

50mm

Step-by-step explanation:

From the smaller to the larger:

Let s + the scale factor

3s = 10  Divide both sides by 3

s = [tex]\frac{10}{3}[/tex]

15[tex](\frac{10}{3})[/tex] = [tex]\frac{150}{3}[/tex] = 50

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