Verified answer

sqrt(32x) + 3*sqrt(8x) ?

I'm assuming the x's are under the radical.

3*sqrt(8x) = sqrt(9*8x) = sqrt(72x)

sqrt(32x) + sqrt(72x) = sqrt(32x + 72x)

sqrt(104x) = sqrt(2*2*2*13*x)

2*sqrt(26x)

√32x + 3√8x

√16(2)x + 3√4(2)x

4√2x + 3(2)√2x

4√2x + 6√2x

10√2x is the answer

10*sqrt(2x)