
In the diagram, GI is a tangent to the circle at H. If EF||GI, calculate the size of ∠EHF
The correct answer is: B
Explanation
<IHF = < EFH = 54º ( alternate angles)
< EHG = < EFH = 54º ( alternate segment)
54º + 54º + < EHF = 180º ( sum of angles in a triangle)
< EHF = 180º - 108º = 72º
There is an explanation video available .