document.write( "Question 173140: Help! My final is on Monday and I can't figure out this word problem. Please write it out step by step so I will be able to do it on the final. Thank you.
\n" ); document.write( "The height of a triangle is 8 centimeters greter than the base. The area of the triangle is 90 square centimeters. Find the length of the base and height of the triangle. Define a variable. Set up a quadratic equation. Solve. Show all work.
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Algebra.Com's Answer #128004 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Let b=base and h=height\r
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\n" ); document.write( "\n" ); document.write( "Since \"The height of a triangle is 8 centimeters greter than the base\", this means that \"h=b%2B8\"\r
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\n" ); document.write( "\n" ); document.write( "Also, remember that the formula for the area of a triangle is \r
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\n" ); document.write( "\n" ); document.write( "\"A=%28b%2Ah%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "Since the \"area of the triangle is 90 square centimeters\", this tells us that \"A=90\"\r
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\n" ); document.write( "\n" ); document.write( "\"90=%28b%28b%2B8%29%29%2F2\" Plug in \"A=90\" (the given area) and \"h=b%2B8\"\r
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\n" ); document.write( "\n" ); document.write( "\"2%2A90=b%28b%2B8%29\" Multiply both sides by 2\r
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\n" ); document.write( "\n" ); document.write( "\"180=b%28b%2B8%29\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"180=b%5E2%2B8b\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"0=b%5E2%2B8b-180\" Subtract 180 from both sides. \r
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\n" ); document.write( "\n" ); document.write( "Notice we have a quadratic equation in the form of \"ab%5E2%2Bbb%2Bc\" where \"a=1\", \"b=8\", and \"c=-180\"\r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for b\r
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\n" ); document.write( "\n" ); document.write( "\"b+=+%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( "\"b+=+%28-%288%29+%2B-+sqrt%28+%288%29%5E2-4%281%29%28-180%29+%29%29%2F%282%281%29%29\" Plug in \"a=1\", \"b=8\", and \"c=-180\"\r
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\n" ); document.write( "\n" ); document.write( "\"b+=+%28-8+%2B-+sqrt%28+64-4%281%29%28-180%29+%29%29%2F%282%281%29%29\" Square \"8\" to get \"64\". \r
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\n" ); document.write( "\n" ); document.write( "\"b+=+%28-8+%2B-+sqrt%28+64--720+%29%29%2F%282%281%29%29\" Multiply \"4%281%29%28-180%29\" to get \"-720\"\r
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\n" ); document.write( "\n" ); document.write( "\"b+=+%28-8+%2B-+sqrt%28+64%2B720+%29%29%2F%282%281%29%29\" Rewrite \"sqrt%2864--720%29\" as \"sqrt%2864%2B720%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"b+=+%28-8+%2B-+sqrt%28+784+%29%29%2F%282%281%29%29\" Add \"64\" to \"720\" to get \"784\"\r
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\n" ); document.write( "\n" ); document.write( "\"b+=+%28-8+%2B-+sqrt%28+784+%29%29%2F%282%29\" Multiply \"2\" and \"1\" to get \"2\". \r
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\n" ); document.write( "\n" ); document.write( "\"b+=+%28-8+%2B-+28%29%2F%282%29\" Take the square root of \"784\" to get \"28\". \r
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\n" ); document.write( "\n" ); document.write( "\"b+=+%28-8+%2B+28%29%2F%282%29\" or \"b+=+%28-8+-+28%29%2F%282%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"b+=+%2820%29%2F%282%29\" or \"b+=++%28-36%29%2F%282%29\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"b+=+10\" or \"b+=+-18\" Simplify. \r
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\n" ); document.write( "\n" ); document.write( "So the possible lengths of the base are \"b+=+10\" or \"b+=+-18\" \r
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\n" ); document.write( "However, a negative base does NOT make sense. So this means that the only possible length for the base is \"b=10\"\r
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\n" ); document.write( "\n" ); document.write( "So the base is 10 centimeters.\r
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\n" ); document.write( "\n" ); document.write( "\"h=b%2B8\" Go back to the height equation (remember the height is 8 cm longer than the base)\r
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\n" ); document.write( "\n" ); document.write( "\"h=10%2B8\" Plug in \"b=10\"\r
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\n" ); document.write( "\n" ); document.write( "\"h=18\" Add\r
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\n" ); document.write( "\n" ); document.write( "So the height is 18 cm\r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "So the base is 10 cm and the height is 18 cm.\r
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\n" ); document.write( "\n" ); document.write( "Check:\r
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\n" ); document.write( "\n" ); document.write( "Area: \"A=%2810%2A18%29%2F2=180%2F2=90\"
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