Question 63691
M^2+14M-58=-7
M^2+14M=-7+58
M^2+14M=51
M^2+14M+49=51+49
(M+7)(M+7)=100
M+7=10
M=10-7
M=3
PROOF
3*3+14*3-58=-7
9+42-58=-7
51-58=-7
-7=-7