Which expression is equal to 4√20−3√45 ? −11√5, √5, 11√5, √-5

4√20 - 3√45
4√(4 * 5) - 3√(9 * 5)
8√5 - 9√5
-√5
It seems this is not one of your answer choices, but having checked it twice, I am sure it is the answer. Did you mistype your question or one of your answers?