Question

Ray GI bisects ∠DGH so that m∠DGI is 3x-9 and m∠IGH is 2x + 21. Find the m< DGI.

Answer 1

Answer:

Since GI bisects that means the angle is cut into 2 equal angles or

DGI = IGH

So

x - 3 = 2x - 13

Solve for x

13 - 3 = 2x - x

10 = x

x = 10

Answer 2

Answer:

$3x - 9 = 2x + 21 \\ 3x - 2x - 9 = 2x - 2x + 21 \\ x - 9 = 21 \\ x - 9 + 9 = 21 + 9 \\ x = 30$

m<DGI = 80°

$3x - 9 = \\ 3(30) - 9 = \\ 90 - 9 = 81$