document.write( "Question 97795This question is from textbook Algebra Structure and Method
\n" ); document.write( ": A poster is 25 cm taller than it is wider. It's mounted on a piece of cardboard so that there is a 5 cm border on all sides. If the area of the border alone is 1350cm^2 what are the dimensions of the poster? \n" ); document.write( "
Algebra.Com's Answer #71285 by ankor@dixie-net.com(22740)\"\" \"About 
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A poster is 25 cm taller than it is wider. It's mounted on a piece of cardboard so that there is a 5 cm border on all sides. If the area of the border alone is 1350cm^2 what are the dimensions of the poster?
\n" ); document.write( ":
\n" ); document.write( "Let x = width of the poster
\n" ); document.write( "then
\n" ); document.write( "(x+25) = length of the poster
\n" ); document.write( ":
\n" ); document.write( "Area of the poster:
\n" ); document.write( "x(x+25) = x^2 + + 25x
\n" ); document.write( ":
\n" ); document.write( "Dimensions of the card board
\n" ); document.write( "Width = x + 2(5) = (x+10
\n" ); document.write( "Length = x+25 + 2(5) = (x+35)
\n" ); document.write( ":
\n" ); document.write( "Area of cardboard:
\n" ); document.write( "(x+35)(x+10) = 0
\n" ); document.write( "x^2 + 45x + 350
\n" ); document.write( ":
\n" ); document.write( "Cardboard area - poster area = border area
\n" ); document.write( "x^2 + 45x + 350 - (x^2 + 25x) = 1350
\n" ); document.write( "x^2 - x^2 + 45x - 25x + 350 = 1350
\n" ); document.write( "20x + 350 = 1350
\n" ); document.write( "20x = 1350 - 350
\n" ); document.write( "20x = 1000
\n" ); document.write( "x = 1000/20
\n" ); document.write( "x = 50 cm is the width of the poster
\n" ); document.write( ":
\n" ); document.write( "50 + 25 = 75 cm is the length of the poster
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "Check using the areas:
\n" ); document.write( "(85*60) - (75*50) =
\n" ); document.write( "5100 - 3750 = 1350 (the given border area}\r
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