11 minutes has passed just subtract
You're lucky that I was able to do this :)
The answer is 
<h3>Answer :</h3>
<u>Given</u> :
- 9(m + 5) - 3(m - 2) = 8m + 31
We have to find value of m
➠ 9(m + 5) - 3(m - 2) = 8m + 31
➠ 9m + 45 - 3m + 6 = 8m + 31
➠ 9m - 3m + 45 + 6 = 8m + 31
➠ 6m + 51 = 8m + 31
➠ 51 - 31 = 8m - 6m
➠ 20 = 2m
➠ m = 20/2
➠<u> m = 10</u>
<h3>Hope It Helps!</h3>
Complementary angels add up to 90°
so x+18°=90°
so x=90-18=72°
The answer is 31 you have to put the numbers in order the cross from low to high then divide by 2 to get 31