Hello!
From the markers in the triangle we know that those two sides are congruent
Since the sides are congruent their opposite angles are congruent
2x + 16 = 3x - 10
Subtract 2x from both sides
16 = x - 10
Add 10 to both sides
26 = x
Put x into the two equations to find the angles
2(26) + 16 = 68
3(26) - 10 = 68
The angles in a triangle add up to 180
Subtract the two know angles from 180 to get the unknown angle
180 - 68 - 68 = 44
The answer is 44°
Hope this helps!