Fh is an angle bisector of the given isosceles triangle, what is the measure of ∠a if ∠c = 55°?
a) 35°
b) 55°
c) 70°
d) 105°

2)
if 2a = 80 and b = c, what is the measure of ∠b?
a) 40°
b) 50°
c) 80°
d) 100°

Part 1) Option A.

Part 2) Option B.

Step-by-step explanation:

we know that

An isosceles triangle has two equal sides and two equal angles

Part 1) what is the measure of ∠a?

we know that

----> equation A

Remember that the sum of the interior angles of triangle is equal to 180 degrees

we have

----> equation B

substitute equation A in equation B

Divide by 2 both sides

we have

---> given problem

substitute

Part b) we have that

we have

---> given problem

---> equation A

Remember that the sum of the interior angles of triangle is equal to 180 degrees

we have

----> equation B

substitute equation A in equation B

we have

substitute