Vertical angles are equal to each other:
∠2 = ∠3
5 + 4y = 6y - 25
→ 30 = 2y
→ 15 = y
∠2 = 5 + 4y = 5 + 4(15) = 5 + 60 = 65
linear pairs equal 180:
∠1 + ∠2 = 180
→ ∠1 + 65 = 180
→ ∠1 = 115
Multiply each term by
b
and simplify.
a = cb
Rewrite the equation as
cb = a
Divide each term by
c
and simplify.
b = a/ c
Answer:
it's also 58°
cause it's an isosceles triangle
