Answer:
AB = 8
Step-by-step explanation:
Given B is the midpoint of AC , then
AB = AC , that is
7x - 6 = 12 - 2x ( add 2x to both sides )
9x - 6 = 12 ( add 6 to both sides )
9x = 18 ( divide both sides by 9 )
x = 2
Then
AB = 7x - 6 = 7(2) - 6 = 14 - 6 = 8
