document.write( "Question 1151211: The length of each side of a square is 3 in. more than the length of each side of a smaller square. The sum of the areas of the squares is 45 in squared . Find the lengths of the sides of the two squares. \n" ); document.write( "
Algebra.Com's Answer #772873 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "Square A has side length x+3
\n" ); document.write( "Square B has side length x
\n" ); document.write( "Square A has a side length 3 units larger compared to the side length of square B.
\n" ); document.write( "Negative side lengths are not possible, so x > 0.\r
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\n" ); document.write( "\n" ); document.write( "Compute the area of square A
\n" ); document.write( "area of square A = (side length of square A)^2
\n" ); document.write( "area of square A = (x+3)^2
\n" ); document.write( "area of square A = (x+3)(x+3)
\n" ); document.write( "area of square A = x(x+3)+3(x+3)
\n" ); document.write( "area of square A = x^2+3x+3x+9
\n" ); document.write( "area of square A = x^2+6x+9
\n" ); document.write( "You could use the FOIL rule to expand out (x+3)^2, but I think the distributive property is more versatile. \r
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\n" ); document.write( "\n" ); document.write( "Compute the area of square B
\n" ); document.write( "area of square B = (side length of square B)^2
\n" ); document.write( "area of square B = x^2\r
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\n" ); document.write( "\n" ); document.write( "Add up the two areas
\n" ); document.write( "total area = (area of square A)+(area of square B)
\n" ); document.write( "total area = (x^2+6x+9)+(x^2)
\n" ); document.write( "total area = 2x^2+6x+9\r
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\n" ); document.write( "\n" ); document.write( "Set this total area equal to 45 and solve for x
\n" ); document.write( "2x^2+6x+9 = 45
\n" ); document.write( "2x^2+6x+9-45 = 0
\n" ); document.write( "2x^2+6x-36 = 0
\n" ); document.write( "2(x^2+3x-18) = 0
\n" ); document.write( "x^2+3x-18 = 0/2
\n" ); document.write( "x^2+3x-18 = 0
\n" ); document.write( "(x+6)(x-3) = 0
\n" ); document.write( "x+6 = 0 or x-3 = 0
\n" ); document.write( "x = -6 or x = 3\r
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\n" ); document.write( "\n" ); document.write( "Since x > 0, this means we only consider x = 3 as the solution.
\n" ); document.write( "If x = 3, then x+3 = 3+3 = 6.\r
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\n" ); document.write( "\n" ); document.write( "Square A has a side length of 6 inches and an area of 36 square inches.
\n" ); document.write( "Square B has a side length of 3 inches and an area of 9 square inches.
\n" ); document.write( "The total area is 36+9 = 45 square inches.
\n" ); document.write( "The answer checks out.
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