Answer:
BC = 26
Step-by-step explanation:
Given that:
B is the midpoint of AC
Then AC = AB + BC
AC = 8x - 20 and AB = 3x - 1
Then,
8x - 20 = (3x - 1) + BC
8x - 20 - (3x - 1) = BC
8x - 20 - 3x + 1 = BC
5x - 19 = BC
But AB = BC
5x - 19 = 3x - 1
5x - 3x = - 1 + 19
2x = 18
x = 9
Hence,
Since BC = AB = 3x - 1
3(9) - 1
27 - 1
= 26