Question 84607
{{{x*sqrt(18)-3*sqrt(8x^2)}}}
First step is to simplify what is under the radicals. For the left term, I know that 18=2*3*3. So I can pull a 3 outside the radical, leaving:
{{{3x*sqrt(2)-3*sqrt(8x^2)}}}
Now, looking at the right term, I know that 8x^2=2*2*2*x*x. That means I can pull out a 2x from under the radical, leaving:
{{{3x*sqrt(2)-6x*sqrt(2)}}}
Notice that you now have sqrt(2) for each term. That means they can be combined. This leaves you with:
{{{highlight(-3xsqrt(2))}}}
Good Luck,
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