Answer:
y = 5
Step-by-step explanation:
The triangle is an isosceles triangle, which means that it has two equal sides and two equal angles.
Therefore, angles B and C are both equal to 75°.
A triangle measures 180°.
75 + 75 + x = 180
150 + x = 180
x = 30°
Angle A has to equal 30°.
(4y + 10)° = 30
4y + 10 - 10 = 30 - 10
4y = 20
y = 5
Hope that helps.
