The answer is C . -7r^2 + 12r -8
100 * pi = pi * r^2
Pi cancels on both sides of the equation
So... 100= r^2
= radius is 10
The estimate between 2 and 9 is 7
Hi!
<h3>Let's do the first step (add 2x). </h3>
5 + 3x + 2x = -2x + 2x + 9
<em>5 + 5x = 9</em>
<h3>Our goal is to isolate x on one side, so the next step would be to subtract 5 (or add -5).</h3>
5 + -5 + 5x = 9 + -5
<u><em>5x = 4</em></u>
<h2>The answer is B. add -5</h2><h3><em>And if you want to finish solving, you would divide by 5 on both sides.</em></h3>
5x/5 = 4/5
x = 0.8
Hope this helps! :)
-Peredhel
