Question

3 sqrt(2x)+x srqt(8x) - 5 sqrt (18x) and she got -10xsqrt (2x)

Part 1: Using complete sentences, explain what Nakim did wrong.

Answer 1

You can't get x multiplied by anything the way the expression stands. It looks like the coefficients of each of the radicals were improperly added. Here is the solution:

3√(2x) + x√(8x) - 5√(18x)
= 3√(2x) + 2x√(2x) - 15√(2x)
= (2x - 12)√(2x)

It seems Nakim did an extra step, adding 2 and -12 to get -10, then tacking on the x afterwards. You can't do that!

Answer 2

o ok i see now that makes so much since thank you so much

Answer 3

Np :)