How do you combine #sqrt18-sqrt8#?

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Answer 1 · 2015-10-21T10:20:26

#sqrt(2)#

#sqrt(18) - sqrt(8)#........................(1)

Write #sqrt(18)" "# as #sqrt(2 times 9) = 3 sqrt(2)#.......(2)

Write #sqrt(8) " "# as #sqrt(2 times 4) = 2sqrt(2)#.........(3)

Substitute (2) and (3) into (1) giving:

#3sqrt(2) - 2sqrt(2)#

3 of something minus 2 of the same thing gives just one of the thing

So #" "3sqrt(2)-2sqrt(2)" " = " "sqrt(2)#