If B is be midpoint of AC, and AC = 8x - 20 find BC

So, we have AB that is 3x-1 and the entire segment AC that is 8x-20

Now, if B is the midpoint, B divides perfectly in half the segment.

AB is as long as BC.

And if you add up AB and BC you get AC.

First of all, BC is our unknown measure.

AB + BC = AC

3x - 1 + BC = 8x - 20

BC = 8x - 20 - (3x - 1)

BC = 8x - 20 - 3x + 1

BC = 5x - 19

We have finally found BC

BC is equal to AC and we can use this formula to find x.

5x - 19 = 3x - 1

5x - 3x = -1 + 19

2x = 18

x = 9

Plug in the value 9.

BC = 5(9) - 19 = 45 - 19 = 26

Answer is BC = 26