document.write( "Question 817230: I really have trouble with word problems! I'd love some help. Thanks! :)
\n" ); document.write( "One number is 3 less than twice another. If their product is 405, find the numbers.
\n" ); document.write( "I tried: x=3-2x, 3-2x=x ??
\n" ); document.write( "I'm just not sure how to do this. \n" ); document.write( "
Algebra.Com's Answer #491959 by rothauserc(4718)\"\" \"About 
You can put this solution on YOUR website!
start with what you are given and then write the related equations
\n" ); document.write( "let the numbers be x and y
\n" ); document.write( "x = 2y - 3
\n" ); document.write( "xy = 405
\n" ); document.write( "substitute for x in second equation
\n" ); document.write( "(2y - 3)y = 405
\n" ); document.write( "2y^2 -3y = 405
\n" ); document.write( "put equation in standard form
\n" ); document.write( "2y^2 -3y -405 = 0
\n" ); document.write( "use quadratic formula to solve for y
\n" ); document.write( "y = (3 + square root(3^2 -4*2*(-405)) / 2*2
\n" ); document.write( "y = (3 - square root(3^2 -4*2*(-405)) / 2*2
\n" ); document.write( "y = 15 or -13.5
\n" ); document.write( "solve for x in first equation
\n" ); document.write( "x = 27 or -30
\n" ); document.write( "check the answers
\n" ); document.write( "15*27 = 405
\n" ); document.write( "(-30)*(-13.5) = 405
\n" ); document.write( "our answers check, therefore there are two solution sets
\n" ); document.write( "x = 27 and y = 15
\n" ); document.write( "x = -30 and y = -13.5\r
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