Question

(2√320 - 7√20 - √45) * 2√5

Answer 1

1) 2V 320 - 7V20 - V45 = 16V5 - 14V5 - 3V5 = - V 5
2) - V 5 • 2 V 5 = - 2 • 5 = - 10

Answer 2

2√320×2√5-7√20×2√5-√45×2√5=4√1600-14√100-2√225=4×40-14×10-2×15=-10