simplify: 3 times the square root of 5 - 2 times the square root of 7 + the square root of 45 - the square root of 28
2 times the square root of 12
2 times the square root of 2
six times the square root of 5 - four times the square root of 7
six times the square root of 10 - four times the square root of 14