document.write( "Question 898084: You have made a quilt that is 3 feet by 4 feet. You want to use the remaining 18 square feet of fabric to add a decorative border of uniform width. What should the width of the border be? Please help ! \n" ); document.write( "

Algebra.Com's Answer #544522 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+x+\"$ = the width of the uniform border
\n" ); document.write( " $\"+x+\"$ gets added twice to both dimensions, so
\n" ); document.write( "I can say:
\n" ); document.write( " $\"+3%2A4+%2B+18+=+%28+3+%2B+2x+%29%2A%28+4+%2B+2x+%29+\"$
\n" ); document.write( " $\"+30+=+12+%2B+8x+%2B+6x+%2B+4x%5E2+\"$
\n" ); document.write( " $\"+4x%5E2+%2B+14x+-+18+=+0+\"$
\n" ); document.write( " $\"+2x%5E2+%2B+7x+-+9+=+0+\"$
\n" ); document.write( "-----------------------
\n" ); document.write( "Use the quadratic formula:
\n" ); document.write( " $\"+x+=+%28+-b+%2B-+sqrt%28+b%5E2+-+4%2Aa%2Ac+%29%29+%2F+%282%2Aa%29+\"$
\n" ); document.write( " $\"+a+=+2+\"$
\n" ); document.write( " $\"+b+=+7+\"$
\n" ); document.write( " $\"+c+=+-9+\"$
\n" ); document.write( " $\"+x+=+%28+-7+%2B-+sqrt%28+7%5E2+-+4%2A2%2A%28-9%29+%29%29+%2F+%282%2A2%29+\"$
\n" ); document.write( " $\"+x+=+%28+-7+%2B-+sqrt%28+49+%2B+72+%29%29+%2F+4+\"$
\n" ); document.write( " $\"+x+=+%28+-7+%2B+sqrt%28+121+%29%29+%2F+4+\"$
\n" ); document.write( " $\"+x+=+%28+-7+%2B+11+%29+%2F+4+\"$
\n" ); document.write( " $\"+x+=+4%2F4+\"$
\n" ); document.write( " $\"+x+=+1+\"$
\n" ); document.write( "The width of the border is 1 ft
\n" ); document.write( "check:
\n" ); document.write( " $\"+30+=+12+%2B+8x+%2B+6x+%2B+4x%5E2+\"$
\n" ); document.write( " $\"+30+=+12+%2B+8%2A1+%2B+6%2A1+%2B+4%2A1+\"$
\n" ); document.write( " $\"+30+=+12+%2B+8+%2B+6+%2B+4+\"$
\n" ); document.write( " $\"+30+=+30+\"$
\n" ); document.write( "OK\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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