Answer:
m<GFC = 149°
Explanation:
m<GFC = m<C + m<CDF (exterior angle theorem)
Substitute
12x - 7 = 26 + 8x + 19
Subtract 8x from each side
12x - 7 - 8x = 26 + 8x + 19 - 8x
4x - 7 = 26 + 19
4x - 7 = 45
Add 7 to both sides
4x - 7 + 7 = 45 + 7
4x = 52
Divide both sides by 4
4x/4 = 52/4
x = 13
✔️m<GFC = 12x - 7
Plug in the value of x
m<GFC = 12(13) - 7 = 149°