The sum of angles in a triangle is 180 degree
First angle + second angle + third angle = 180
From the given diagram , AC = BC
The angle opposite to the sides are also equal
So angle A and angle B are equal
Angle A = 50 so angle B = 50 degree
angle B = 2x = 50
Divide both sides by 2
So x= 25 degree
Angle A + angle B + angle C = 180
50 + 50 + 5y + 10 = 180
100 + y + 10 = 180
110 + 5y = 180
Subtract 110 on both sides
5y = 70
now divide both sides by 5
The value of y = 14