help me

Question

help me

marissabartoldo · Answer

attachment

marissabartoldo · Answer

@snowflake0531

newdawn1 · Answer

@snowflake0531

jhonyy9 · Answer

V = pi×r^2 ×h/3

from this equation you need find the r value

on the left side substitute this quadratic of V 
h = 6 
on the left side factorize out the pi 
divide both sides by pi 
and after these steps look what will get 
please post it here

marissabartoldo · Answer

that doesn't make sense

marissabartoldo · Answer

@snowflake0531

Imagine · Answer

If you're more of a visual learner. Here you are:
$$V=\pi \times r^2 \times h/3$$
Substitute as Jhonyy Said.:
$$V=\pi \times r^2 \times 6/3$$
Simplify that 6/3.:
$$V=\pi \times r^2 \times 2$$
Divide both sides by Pi.:
$$V/\pi=r^2 \times 2$$
This is what it looks like at the last step of @jhonyy9's explanation.

jhonyy9 · Answer

@imagine wrote:

If you're more of a visual learner. Here you are: $$V=\pi \times r^2 \times h/3$$ Substitute as Jhonyy Said.: $$V=\pi \times r^2 \times 6/3$$ Simplify that 6/3.: $$V=\pi \times r^2 \times 2$$ Divide both sides by Pi.: $$V/\pi=r^2 \times 2$$ This is what it looks like at the last step of @jhonyy9's explanation.

yes but i ve said above that in place of V substitute this quadratic expression of V from what you can factorize out the pi and in this way you can divide both sides by pi

Imagine · Answer

$$\frac{ V }{ \pi }=\frac{ r^2\times2 }{ \pi}$$
Like this jhonyy?

jhonyy9 · Answer

@imagine wrote:

$$\frac{ V }{ \pi }=\frac{ r^2\times2 }{ \pi}$$ Like this jhonyy?

on the right side no so like you above wrote to eliminate - simplify - pi on both sides but to see it please substitute this expression of V

jhonyy9 · Answer

@jhonyy9 wrote:

@imagine wrote:

If you're more of a visual learner. Here you are: $$V=\pi \times r^2 \times h/3$$ Substitute as Jhonyy Said.: $$V=\pi \times r^2 \times 6/3$$ Simplify that 6/3.: $$V=\pi \times r^2 \times 2$$ Divide both sides by Pi.: $$V/\pi=r^2 \times 2$$ This is what it looks like at the last step of @jhonyy9's explanation.

yes but i ve said above that in place of V substitute this quadratic expression of V from what you can factorize out the pi and in this way you can divide both sides by pi

like here but in place of V if use this quadrilateral so then on the left side you can simplifie pi too

GoodFellow · Answer

Please clarify where you are stuck in getting the answer: how far have you tried?

marissabartoldo · Answer

I need help with the whole thing

GoodFellow · Answer

breakdown the question with the knowns & unknowns first

marissabartoldo · Answer

knowns and unknowns?

GoodFellow · Answer

Yes, what you are given\know and what is to be found
Then try to build a connection among the quantities
Now, the Volume is known and the radius (in terms of x) is to be found

GoodFellow · Answer

Think, the volume is given and on the other hand, there is the general equation used to find the volume of a cone and you are asked to find r
.

marissabartoldo · Answer

ok so how do I find r

GoodFellow · Answer

fine, can you type the connection that u were able to create

GoodFellow · Answer

$$\begin{aligned}V= \frac{1}{3} \pi r^2 h &= 8\pi x^2+24 \pi x +18 \pi\ \frac{1}{3}\pi r^2 h&=2\pi (4 x^2 +12x+9) \ \frac{1}{3}\pi r^2 h&= 2\pi (2x+3)(2x+3)\\frac{1}{3}\pi r^2 h&= 2\pi (2x+3)^2\\frac{1}{3}\cancel{\pi}r^2 h&=2\cancel{\pi}(2x+3)^2\r^2&=\frac{6}{h}(2x+3)^2\ \text{h = 6:  we are given} \ r^2 &=(2x+3)^2\ r&=\sqrt{(2x+3)^2} \ &=2x+3 \end{aligned}$$

GoodFellow · Answer

Study well at a later time. It's all about getting a connection between the given quantities, after that it's just the basic math. Good Luck.

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