document.write( "Question 346901: I need help solving the following using the substitution method and the elimination method. I am so stuck trying to figure these out.\r
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document.write( "4x+3y=48
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document.write( "3x+2y=34 \n" );
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Algebra.Com's Answer #248120 by ankor@dixie-net.com(22740)![]() ![]() You can put this solution on YOUR website! solve the following using the substitution method and the elimination method. \n" ); document.write( ": \n" ); document.write( "4x+3y=48 \n" ); document.write( "3x+2y=34 \n" ); document.write( ": \n" ); document.write( "Use the 2nd equation for substitution \n" ); document.write( "3x + 2y = 34 \n" ); document.write( "2y = -3x + 34 \n" ); document.write( "Divide both sides by 2 \n" ); document.write( "y = \n" ); document.write( "y = -1.5x + 17 \n" ); document.write( ": \n" ); document.write( "Substitute (-1.5x+17) for y in the 1st equation \n" ); document.write( "4x + 3(-1.5x + 17) = 48 \n" ); document.write( "4x - 4.5x + 51 = 48 \n" ); document.write( "4x - 4.5y = 48 - 51 \n" ); document.write( "-.5x = -3 \n" ); document.write( "x has to be positive, multiply both sides by -1 \n" ); document.write( ".5x = 3 \n" ); document.write( "x = \n" ); document.write( "x = 6 \n" ); document.write( "find y using y = -1.5x+17 \n" ); document.write( "y = -1.5(6) + 17 \n" ); document.write( "y = -9 + 17 \n" ); document.write( "y = +8 \n" ); document.write( "Check solutions in the 2nd equation; 3x+2y=34 \n" ); document.write( "3(6) + 2(8) = 34 \n" ); document.write( "18 + 16 = 34 \n" ); document.write( "34 = 34; confirms our solutions \n" ); document.write( ": \n" ); document.write( ": \n" ); document.write( "By elimination \n" ); document.write( "4x+3y=48 \n" ); document.write( "3x+2y=34 \n" ); document.write( "Multiply the 1st equation by 2, and the 2nd equation by 3 \n" ); document.write( "8x + 6y = 96 \n" ); document.write( "9x + 6y = 102 \n" ); document.write( "------------------subtraction eliminates y, find x \n" ); document.write( "-1x = -6 \n" ); document.write( "x = 6; mult by -1 \n" ); document.write( ": \n" ); document.write( "You can find y using either equation, replacing x with 6 \n" ); document.write( " |