Answer:
Explanation:
Sum of all angles of triangle = 180
8x -18 + 6x - 4 + 5x - 7 = 180
8x + 6x + 5x - 18 - 4 - 7 = 180
Combine like terms
19x - 29 = 180
Add 29 to both sides
19x = 180 +29
19x = 209
Divide both sides by 19
x = 209/19
x = 11
∠F = 5x - 7
= 5*11 - 7
= 55 - 7
∠F = 48°