Answer:
50
Explanation:
We know that the sum of the angles of a triangle is 180
HCA + CAH + AHB = 180
80+ CAH + 90 = 180
Combine like terms
170 + HAC = 180
HAC= 180-170
HAC = 10
We also know that HCA + ACB is a straight line so it adds to 180
HCA + ACB = 180
80+ACB = 180
ACB = 180-80
ACB = 100
Since ACB is isosceles the base angles have the same measure so CAB = ABC
We know that the sum of the angles of a triangle is 180
CAB + ABC + ACB = 180
Replacing ABC with CAB
CAB + CAB + 100 = 180
2CAB + 100 =180
2 CAB = 180-100
2 CAB = 80
Divide by 2
CAB = 80/2
CAB = 40
Now find HAB
HAB = HAC + CAB
= 10 + 40
= 50