Answer:
see explanation
Step-by-step explanation:
Since 2 sides of the triangle are congruent then the triangle is isosceles.
Thus the 2 base angles are congruent, that is
∠2 = 39, that is
4x + 7 = 39 ( subtract 7 from both sides )
4x = 32 ( divide both sides by 4 )
x = 8
