document.write( "Question 519719: Twice the square of a certain number added to 3times the number makes 90.find the number \n" ); document.write( "

Algebra.Com's Answer #345742 by oberobic(2304) $\"\"$ $\"About$

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x = a certain number
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\n" ); document.write( "2x^2 +3x = 90
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\n" ); document.write( "2x^2 +3x -90 = 0
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\n" ); document.write( "factor
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\n" ); document.write( "(2x +15)(x -6) = 0
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\n" ); document.write( "x = -15/2 or 6
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\n" ); document.write( " $\"+graph%28500%2C500%2C-10%2C10%2C-100%2C100%2C2%2Ax%5E2%2B3%2Ax-90%29+\"$ \n" ); document.write( "

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