A= -81 + square root of 113
a<span>≈</span> -70.36985418
using the LCD method.... well, there are a couple of ways, but let's simply add them up.
well, the denominators are 5x and 2x... so the only LCD will just be 10x, since it's divisible by both, so let's use that one.

Midpoint
We know AC is a segment and B is its midpoint. This means the length of the segment AB is half the length of the segment AC. This also means the length of the segment BC is half the length of AC, and equal to AB.
This can be visualized as follows:
Since AB=7, then BC = 7 and AC=AB+BC = 14
Answer: BC = 7, and AC=!4
Hi there!
Your question:
Sales fall from 300 per week to 270 per week what's the percentage change?
My answer:
The formula for calculating percent change is as follows:
[(y2 - y1)/y1]*100=your percent change
y2= first value
y1=second value
Plug the numbers in:
[(300-270)/300]*100
[30/300]*100
0.1*100
10
Therefore, the percent change is 10%
Hope this helps! Let me know if it's incorrect so I can fix it:)