(7m2-2n)2 te twos stand forpower

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:

you can use a^2+ b^2=c^2

he is going to fill two shelves and the third shelf will only have five video games