document.write( "Question 333636: I am having a lot of trouble with this question: \"The area of a rectangle is 528 sq mm. The base is 8 more than three times the height. What is the perimeter?\" I started the problem by setting up this equation: 528=h(3h+8) where h=height. Then I got 528=3h^2+8h. However, I'm not sure what to do after this. \n" ); document.write( "
Algebra.Com's Answer #239051 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"528=3h%5E2%2B8h\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"0=3h%5E2%2B8h-528\" Subtract 528 from both sides.\r
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\n" ); document.write( "\n" ); document.write( "Notice that the quadratic \"3h%5E2%2B8h-528\" is in the form of \"Ah%5E2%2BBh%2BC\" where \"A=3\", \"B=8\", and \"C=-528\"\r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for \"h\":\r
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\n" ); document.write( "\n" ); document.write( "\"h+=+%28-B+%2B-+sqrt%28+B%5E2-4AC+%29%29%2F%282A%29\" Start with the quadratic formula\r
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\n" ); document.write( "\n" ); document.write( "\"h+=+%28-%288%29+%2B-+sqrt%28+%288%29%5E2-4%283%29%28-528%29+%29%29%2F%282%283%29%29\" Plug in \"A=3\", \"B=8\", and \"C=-528\"\r
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\n" ); document.write( "\n" ); document.write( "\"h+=+%28-8+%2B-+sqrt%28+64-4%283%29%28-528%29+%29%29%2F%282%283%29%29\" Square \"8\" to get \"64\". \r
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\n" ); document.write( "\n" ); document.write( "\"h+=+%28-8+%2B-+sqrt%28+64--6336+%29%29%2F%282%283%29%29\" Multiply \"4%283%29%28-528%29\" to get \"-6336\"\r
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\n" ); document.write( "\n" ); document.write( "\"h+=+%28-8+%2B-+sqrt%28+64%2B6336+%29%29%2F%282%283%29%29\" Rewrite \"sqrt%2864--6336%29\" as \"sqrt%2864%2B6336%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"h+=+%28-8+%2B-+sqrt%28+6400+%29%29%2F%282%283%29%29\" Add \"64\" to \"6336\" to get \"6400\"\r
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\n" ); document.write( "\n" ); document.write( "\"h+=+%28-8+%2B-+sqrt%28+6400+%29%29%2F%286%29\" Multiply \"2\" and \"3\" to get \"6\". \r
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\n" ); document.write( "\n" ); document.write( "\"h+=+%28-8+%2B-+80%29%2F%286%29\" Take the square root of \"6400\" to get \"80\". \r
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\n" ); document.write( "\n" ); document.write( "\"h+=+%28-8+%2B+80%29%2F%286%29\" or \"h+=+%28-8+-+80%29%2F%286%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"h+=+%2872%29%2F%286%29\" or \"h+=++%28-88%29%2F%286%29\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"h+=+12\" or \"h+=+-44%2F3\" Simplify. \r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"h+=+12\" or \"h+=+-44%2F3\" \r
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\n" ); document.write( "\n" ); document.write( "However, a negative height doesn't make any sense. So we'll ignore \"h+=+-44%2F3\"\r
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\n" ); document.write( "\n" ); document.write( "This means that the height is 12 mm.\r
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\n" ); document.write( "\n" ); document.write( "I'll let you use this info to find the perimeter.
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