document.write( "Question 55894: QUESTION: SOLVE THE SYTEM BY ADDITION\r
\n" );
document.write( "\n" );
document.write( "-5X+2Y=10
\n" );
document.write( "X-3Y=11 \n" );
document.write( "
Algebra.Com's Answer #37902 by junior403(76)![]() ![]() ![]() You can put this solution on YOUR website! SOLVE THE SYTEM BY ADDITION\r \n" ); document.write( "\n" ); document.write( "-5X+2Y=10 \n" ); document.write( "X-3Y=11\r \n" ); document.write( "\n" ); document.write( "First we can add these equations vertically. \n" ); document.write( "-5X+2Y=10 \n" ); document.write( "....X-3Y=11 \n" ); document.write( "__________ \n" ); document.write( "-4X-1Y=21 \n" ); document.write( "Ok so far? \n" ); document.write( "Now we can solve this result for one of the variables. Lets choose Y. \n" ); document.write( "-4X-Y=21 \n" ); document.write( "We can add 4X to both sides to move it to the right. \n" ); document.write( "-Y=21+4X \n" ); document.write( "Then we can divide each side of the equation by -1 to make the Y positive. \n" ); document.write( "Y=-21-4X \n" ); document.write( "Now that we have the value for Y we can insert that value into one of our original equations. \n" ); document.write( "X - 3(-21-4X) = 11 \n" ); document.write( "Ok? \n" ); document.write( "Now we can solve for X. \n" ); document.write( "first we can distribute the -3 with everything inside the parentesis. \n" ); document.write( "X + 63 +12X = 11 \n" ); document.write( "Then we can subtract 63 from both sides. \n" ); document.write( "X + 12X = -52 \n" ); document.write( "Then we combine like terms. \n" ); document.write( "13X = -52 \n" ); document.write( "Then we can divide both sides by 13. \n" ); document.write( "X = -4 \n" ); document.write( "Now that we know the value of X, we can substitute the -4 in the other original equation. \n" ); document.write( "-5(-4)+2Y=10 \n" ); document.write( "Distribute. \n" ); document.write( "20 + 2Y = 10 \n" ); document.write( "Subtract 20 from both sides. \n" ); document.write( "2Y = -10 \n" ); document.write( "Divide by 2. \n" ); document.write( "Y = -5 \n" ); document.write( "So X = -4 and Y = -5 \n" ); document.write( "To check this we can apply both results to one or both of the originals. \n" ); document.write( "-5X+2Y=10 \n" ); document.write( "-5(-4)+2(-5)=10 \n" ); document.write( "20 -10 = 10 TRUE \n" ); document.write( "X-3Y=11 \n" ); document.write( "(-4)-3(-5)=11 \n" ); document.write( "-4 + 15 = 11 TRUE \n" ); document.write( "I hope this helps. \n" ); document.write( "Good Luck! \n" ); document.write( " \n" ); document.write( " |