SOLUTION: can you help me simplify by combining like terms? sqrt{{{63}}}-2sqrt{{{28}}}+5sqrt{{{7}}}

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Question 77913: can you help me simplify by combining like terms?
sqrt63-2sqrt28+5sqrt7
Answer by bucky(2189) About Me  (Show Source):
You can put this solution on YOUR website!
sqrt%2863%29-2%2Asqrt%2828%29%2B5%2Asqrt%287%29
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In each square root look for factors that are squares.
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sqrt%289%2A7%29-+2%2Asqrt%284%2A7%29%2B5%2Asqrt%287%29
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Notice that 9 in the first square root and 4 in the second square root are squares.
Split the squares using the product rule for square roots to get:
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sqrt%289%29%2Asqrt%287%29+-+2%2Asqrt%284%29%2Asqrt%287%29+%2B+5%2Asqrt%287%29
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Take the square root of 9 and the square root of 4 to reduce the expression to:
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3%2Asqrt%287%29+-+2%2A2%2Asqrt%287%29+%2B+5%2Asqrt%287%29
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Multiply the 2*2:
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3%2Asqrt%287%29+-+4%2Asqrt%287%29+%2B+5%2Asqrt%287%29
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Factor the sqrt%287%29 from each of the three terms to get:
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%283+-+4+%2B+5%29%2Asqrt%287%29
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Combine the terms inside the parentheses to get +4 and the expression finally becomes:
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4%2Asqrt%287%29
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That's the answer. Cheers!