Answer:
BFG = 135
Explanation:
The angles are alternate interior angles and alternate interior angles are equal when the lines are parallel
3x+15 = 5x-5
Subtract 3x from each side
3x+15-3x = 5x-5-3x
15 = 2x-5
Add 5 to each side
15+5 = 2x-5+5
20 = 2x
Divide by 2
20/2 = 2x/2
10 =x
We know that AFG + BFG = 180 since it forms a straight line
AFG + BFG = 180
3x+15 + BFG = 180
3(10) + 15 + BFG = 180
30+15 + BFG = 180
45 + BFG = 180
BFG = 180-45
BFG = 135