In the equation x^2 mx n = 0, m and n are integers. the only possible value for x is –3. what is the value of m ?
a. 3
b. –3
c. 6
d. –6
e. 9

take the logarithm of both sides (the base of the log doesn't matter):

apply the exponent property - this says that :

distribute the log terms on both sides:

group like terms together:

divide through both sides by the coefficient on :

you can do some additional rewriting here using the properties of the logarithm to simplify things if you like: