Answer:
AB = 105
Explanation:
Since ∠ A and ∠ B are equal then Δ ABC is isosceles with 2 congruent legs.
AC = BC , substitute values
6x - 7 = 5x + 7 ( subtract 5x from both sides )
x - 7 = 7 ( add 7 to both sides )
x = 14
Then
AB = 7x + 7 = 7(14) + 7 = 98 + 7 = 105