document.write( "Question 206593: A designer attempts to arrange the characters of his artwork in the form of a square grid with equal numbers of rows and columns, but finds that 24 characters are left out. When he tries to add one more row and column, he finds that he has 25 too few characters. Find the number of characters used by the designer.\r
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Algebra.Com's Answer #156149 by Marth(57)\"\" \"About 
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let x = the width of the grid.
\n" ); document.write( "\"x%5E2+%2B24\" = the number of characters
\n" ); document.write( "\"%28x%2B1%29%5E2+-25\" = the number of characters.
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\n" ); document.write( "You can solve this algebraically, or using properties of squares, which is faster.
\n" ); document.write( "For any two numbers \"a\" and \"b\" such that \"a%2B1+=+b\", \"b%5E2-a%5E2=a%2Bb\"
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\n" ); document.write( "Here we have \"x%5E2%2B24=%28x%2B1%29%5E2-25\"
\n" ); document.write( "\"24%2B25+=+%28x%2B1%29%5E2-x%5E2\", which matches the difference of two squares above.
\n" ); document.write( "So, x=24 and x+1 = 25.
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\n" ); document.write( "To find the number of characters, use either value in the equations obtained at the start.
\n" ); document.write( "\"x%5E2+%2B24\" = the number of characters
\n" ); document.write( "= \"24%5E2+%2B+24\"
\n" ); document.write( "= \"576+%2B+24\"
\n" ); document.write( "=600
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