What is the radius and diameter of the following circle?<br> 7.5 cm

Someone help me with my math homework pleaseee. Find the volumes of the pyramids and the height is 7cm for the first one.

gregori [183]

$\bf \textit{volume of a pyramid}\\\\
V=\cfrac{1}{3}Bh\qquad 
\begin{cases}
B=\textit{area of the base}\\
h=height
\end{cases}$

now, the first one, on the far-left.... can't see the height.. but I gather you do, now as far as its Base area, well, the bottom is just a 12x12 square, so the area of its base is just 12*12

now, the middle pyramid, has a height of 6, the base is also a square, 8x8, so the Base area is just 8*8

now the last one on the far-right

has a height of 8, the Base is a Hexagon, with sides of 6

$\bf \textit{area of a regular polygon}\\\\
A=\cfrac{1}{4}ns^2cot\left( \frac{180}{n} \right)\qquad 
\begin{cases}
n=\textit{number of sides}\\
s=\textit{length of one side}\\
\frac{180}{n}=\textit{angle in degrees}\\
----------\\
n=6\\
s=6
\end{cases}\\\\\\ A=\cfrac{1}{4}\cdot 6\cdot 6^2\cdot cot\left( \frac{180}{6} \right)$

5 0

2 years ago

How do I solve for constant rate of change

barxatty [35]

You use the slope formula, (y2-y1/x2-x1)

6 0

3 years ago

What is the slope of this graph? −14 4 14 −4 Number graph ranging from negative 10 to 10 on both the x and y axis. A line passes

spin [16.1K]

The slope of this graph is - 4

Step-by-step explanation:

The slope of a line is $m=\frac{y_{2}-y_{1}}{x_{2}-x_{1}}$ , where

$(x_{1},y_{1})$ and $(x_{2},y_{2})$ are two points on the line
The slope of a horizontal line is zero
The slope of a vertical line is undefined

∵ The graph is a line

∵ The line passes through points (1 , -2) and (0 , 2)

∴ $x_{1}$ = 1 and $x_{2}$ = 0

∴ $y_{1}$ = -2 and $y_{2}$ = 2

- Substitute these values in the rule below

∵ $m=\frac{y_{2}-y_{1}}{x_{2}-x_{2}}$

∴ $m=\frac{2--2}{0-1}=\frac{4}{-1}$

∴ m = - 4

The slope of this graph is - 4

Learn more:

You can learn more about the slope of a line in brainly.com/question/4152194

#LearnwithBrainly

7 0

3 years ago

Read 2 more answers

An aquarium with a square base has no top. There is a metal frame. Glass costs 8 dollars/m^2 and the frame costs 7 dollars/m. Th

Irina-Kira [14]

Given that the volume of the aquarium is 20m^3.

Volume = Area of Base x height

Area of Base = Volume / height = 20/h

Given that the aquarium has a square base.

Area of square = l^2

Thus, the length of the base of the aquarium is $\sqrt{area \ of \ base} = \sqrt{ \frac{20}{h} }$

The frame is to cover 8 sides with the length equal to the length of the base and 4 sides with the length of the height.

Thus, the total perimeter of the frame is given by $8\sqrt{\frac{20}{h}}+4h= \sqrt{64\left(\frac{20}{h}\right)}+4h = \sqrt{\frac{1,280}{h}}+4h$

Area of the four side faces of the aquarium is 4 times the length of the base times the height = $4\times\sqrt{ \frac{20}{h} }\times h=\sqrt{16\left(\frac{20}{h}\right)h^2}=\sqrt{320h}$

Total area to be covered by grass is the base and the four side faces and is given by $\frac{20}{h}+\sqrt{320h}$

Cost of the entire metal frame = $7\left(\sqrt{\frac{1,280}{h}}+4h\right)= \sqrt{49\left(\frac{1,280}{h}\right)}+7(4h) = \sqrt{\frac{62,720}{h}}+28h$

Cost of the entire grass = $8\left(\frac{20}{h}+\sqrt{320h}\right)=\frac{160}{h}+\sqrt{64(320h)}=\frac{160}{h}+\sqrt{20,480h$

Therefore, total cost in terms of the height, h, is given by

$C=\sqrt{\frac{62,720}{h}}+28h+\frac{160}{h}+\sqrt{20,480h$

3 0

3 years ago

If 4 apples cost 0.80, how much do 12 apples cost

Neporo4naja [7]

4 / 0.80 = 12 / x...cross multiply
4x = 0.80 * 12
4x = 9.6
x = 9.6 / 4
x = 2.4.....12 apples cost $ 2.40

3 0

3 years ago

Read 2 more answers

What is the radius and diameter of the following circle? 7.5 cm