Question

8. Simplify and solve this equation: 4m + 9 + 5m – 12 = 42. A. m = 5 B. m = –5 C. m = 4 D. m = -4

Answer 1

4m+9+5m-12=42 9m-3=42 Divide bothsides by 9. 9m/9 -3/9=-0.3=-4 m=-4

Answer 2

4m+9+5m-12=42
Combine 9 and -12 and you get -3 so
4m+5m-3=42
And then combine 4m and 5m and you get 9m so
9m-3=42
And then add three on both sides (canceling out the -3) leaving you with
9m=45
And then divide 45 by 9 and you get 5 so
m=5.
The answer is A. M=5