document.write( "Question 1008217: What is the answer to (5c-1)(5c+1) \n" ); document.write( "
Algebra.Com's Answer #623991 by Theo(13342)\"\" \"About 
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(a-b) * (a+b) = a^2 - b^2\r
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\n" ); document.write( "\n" ); document.write( "by that rule, (5c-1)*(5x+1) should be equal to (5c)^2 - (1)^2 which is equal to 5^2c^2 - 1^2 which is equal to 25c^2 - 1.\r
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\n" ); document.write( "\n" ); document.write( "let's see if that works.\r
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\n" ); document.write( "\n" ); document.write( "using the distributive law of multiplication:\r
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\n" ); document.write( "\n" ); document.write( "(5c-1)*(5c+1) = 5c*5c + 1*5c - 1*5c - 1*1\r
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\n" ); document.write( "\n" ); document.write( "the + 1*5x and the - 1*5x cancel out and you are left with:\r
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\n" ); document.write( "\n" ); document.write( "5c*5c - 1*1 which is equal to (5c)^2 - 1^2 which is equal to 5^2*c^2 - 1 which is equal to 25c^2 - 1.\r
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\n" ); document.write( "\n" ); document.write( "the rule works.\r
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\n" ); document.write( "\n" ); document.write( "if you recognize the pattern, you can apply the rule.\r
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\n" ); document.write( "\n" ); document.write( "if you don't, then you just multiply the factors as you would normally and you will get the same result.\r
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