document.write( "Question 964264: The height of a triangle is 2 centimeters less than its base. If the area of the triangle is 28 square centimeters, find the base and height of the triangle. Round to the nearest tenth of a centimeter if necessary. \n" ); document.write( "
Algebra.Com's Answer #589141 by macston(5194)\"\" \"About 
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b=base; h=height=b-2cm
\n" ); document.write( "\"A=%281%2F2%29bh\" Substitute for h.
\n" ); document.write( "\"A=%281%2F2%29%28b%29%28b-2cm%29\"
\n" ); document.write( "\"28cm%5E2=%281%2F2%29%28b%29%28b-2cm%29\" Multiply each side by 2.
\n" ); document.write( "\"56cm%5E2=b%5E2-2b\" Subtract 56 from each side.
\n" ); document.write( "\"0=b%5E2-2b-56\"
\n" ); document.write( "\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ab%5E2%2Bbb%2Bc=0\" (in our case \"1b%5E2%2B-2b%2B-56+=+0\") has the following solutons:
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\n" ); document.write( " \"b%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
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\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
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\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%28-2%29%5E2-4%2A1%2A-56=228\".
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\n" ); document.write( " Discriminant d=228 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--2%2B-sqrt%28+228+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"b%5B1%5D+=+%28-%28-2%29%2Bsqrt%28+228+%29%29%2F2%5C1+=+8.54983443527075\"
\n" ); document.write( " \"b%5B2%5D+=+%28-%28-2%29-sqrt%28+228+%29%29%2F2%5C1+=+-6.54983443527075\"
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\n" ); document.write( " Quadratic expression \"1b%5E2%2B-2b%2B-56\" can be factored:
\n" ); document.write( " \"1b%5E2%2B-2b%2B-56+=+1%28b-8.54983443527075%29%2A%28b--6.54983443527075%29\"
\n" ); document.write( " Again, the answer is: 8.54983443527075, -6.54983443527075.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B-2%2Ax%2B-56+%29\"

\n" ); document.write( "\n" ); document.write( "ANSWER 1: The base is 8.55 cm. (This would round to 8.5cm- kept extra digit for check)
\n" ); document.write( "h=b-2cm=8.55cm=6.55 cm (see above)
\n" ); document.write( "ANSWER 2: The height is 6.55 cm.
\n" ); document.write( "CHECK:
\n" ); document.write( "\"A=%281%2F2%29bh\"
\n" ); document.write( "\"28cm%5E2=%281%2F2%29%288.55cm%29%286.55cm%29\"
\n" ); document.write( "\"28cm%5E2=%281%2F2%29%2856.00cm%5E2%29\"
\n" ); document.write( "\"28cn%5E2=28cm%5E2\"
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