Question 199837
13 sqrt20 -15 sqrt32 -8sqrt45+7sqrt8
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factor  all  radicals  for  largest  perfect  square
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13 sqrt( 4*5) -15 sqrt(16*2) -8sqrt(9*5) +7sqrt(4*2)
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13 sqrt4 * sqrt5 - 15 sqrt16 *sqrt2 -8sqrt9*sqrt5 +7 sqrt4*sqrt2
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13*2sqrt5 -15*4sqrt2 -8*3sqrt5 +7*2sqrt2
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collect  like  terms
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26 sqrt5 -24sqrt5   -60sqrt2 +14 sqrt2
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2 sqrt5 -46 sqrt2
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check  using  calculator  on  original  and  answer,,,,both  =  -60.58,,,,,ok