document.write( "Question 401529: the length of a rectangle is is 10m less than twise the width..what are dimension s of this rectangle if the area is 72m^2 \n" ); document.write( "

Algebra.Com's Answer #284137 by Tatiana_Stebko(1539) $\"\"$ $\"About$

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Let x is the width of a rectangle,
\n" ); document.write( "The length of a rectangle is 10m less than twice the width, so the lenght is $\"%282x-10%29\"$ m
\n" ); document.write( "The area of rectangle is $\"x%2A%282x-10%29\"$ , from text the area is 72m^2
\n" ); document.write( "equation
\n" ); document.write( " $\"x%2A%282x-10%29=72\"$
\n" ); document.write( " $\"2x%5E2-10x=72\"$
\n" ); document.write( " $\"2x%5E2-10x-72=0\"$ divide both sides by 2
\n" ); document.write( " $\"x%5E2-5x-36=0\"$ quadratic equation
\n" ); document.write( " $\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"$
\n" ); document.write( " $\"x+=+%28-%28-5%29+%2B-+sqrt%28+%28-5%29%5E2-4%2A1%2A%28-36%29%29%29%2F%282%2A1%29+\"$
\n" ); document.write( " $\"x+=+%285+%2B+sqrt%28+169%29%29%2F2+\"$ or $\"x+=+%285-+sqrt%28+169%29%29%2F2+\"$
\n" ); document.write( " $\"x+=+%285+%2B+13%29%2F2+\"$ or $\"x+=+%285-+13%29%2F2+\"$
\n" ); document.write( " $\"x+=+18%2F2+\"$ or $\"x+=+-+8%2F2+\"$
\n" ); document.write( " $\"x+=9+\"$ or $\"x+=+-+4+\"$ <0,extraneous root of the equation does not satisfy the conditions of the problem
\n" ); document.write( "So width of a rectangle is 9 m, the length of a rectangle is $\"%282x-10%29=%282%2A9-10%29=8\"$ m
\n" ); document.write( "Answer 9 m and 8 m \n" ); document.write( "

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