i need help eith this problem?

Question

3(root18)-2(root32)-5(root50). i just need to understand how to do it.

Answer 1

You need to simplify the radicals. That means finding the perfect square factors.

sqrt(18) = sqrt(2 * 9)

9 is a perfect square and 2 is prime, so

sqrt(18) = 3 sqrt(2)

Similarly,

sqrt(32) =sqrt(2 * 16) = 4 sqrt(2)

sqrt(50) = sqrt(2 * 25) = 5 sqrt(2)

So your problem becomes

3 * 3 sqrt(2) - 2 * 4 sqrt(2) - 5 * 5 sqrt(2) =

9 sqrt(2) - 8 sqrt(2) - 25 sqrt(2) = -24 sqrt(2)