Hello there!
If you look at the picture of the triangle, you would see that line EF and line FG have same length of 6.
A triangle that has two sides of equal length is called isosceles triangle.
So your triangle is an isosceles triangle!
An isosceles triangle has two angles on facing each other are same.
For example, the ∠E is 28°. Then what is the angle that is on the opposite side of ∠E? It is ∠G.
∠G would be 28°.
So your answer is C. 28°
In some questions, they might ask you for the measure of ∠F.
The sum of all three angles of a triangle must equal to 180°.
Since you know the two of the angles, ∠E and ∠G, you can find ∠F easily.
∠E + ∠F + ∠G = 180°
28° + ∠F + 28° = 180°
∠F + 56° = 180°
∠F = 124°
Hope this helped!!! :)