Since the x's both are to a power and have exponents outside of the parenthesis, we multiply the inner exponent by the outer exponent.
x^-150 / x^-144
Then, we need to move the bottom term to the top so that we have no negative exponents. Now, we are technically subtracting, but subtracting a negative is the same thing as adding.
x^(-150 + 144)
x^-6
Hope this helps!