Answer:
AB = 5
Step-by-step explanation:
Since Δ ABC is isosceles then BC = AB, that is
5x - 10 = 3x - 4 ( subtract 3x from both sides )
2x - 10 = - 4 ( add 10 to both sides )
2x = 6 ( divide both sides by 2 )
x = 3
Thus
AB = 3x - 4 = 3(3) - 4 = 9 - 4 = 5
