6 times the square root of 20 plus 8 times the square root of 5 minus 5 times the square root of 45

6√20 + 8√5 - 5√45  =

6√(4*5) + 8√5 - 5√(9*5) =

6(2)√5 + 8√5 - 5(3)√5 =

12√5 + 8√5 - 15√5 =

20√5 - 15√5 =

5√5