document.write( "Question 432939: solve by subsitution method 2x+8y=6 4x+8y= -36 \n" ); document.write( "
Algebra.Com's Answer #300091 by Lstark01(4)![]() ![]() ![]() You can put this solution on YOUR website! 2x+8y=6 and 4x+8y= -36\r \n" ); document.write( "\n" ); document.write( "Take the first equation and solve for x or y. I will solve for y. \n" ); document.write( "2x+8y=6 \n" ); document.write( "-2x on both sides \n" ); document.write( "8y = -2x+6 \n" ); document.write( "divide by 8 on both sides \n" ); document.write( "y = -.25x + .75 \n" ); document.write( "Take this equation and substitute it in for y in the other equation and solve for x:\r \n" ); document.write( "\n" ); document.write( "4x + 8(-.25x + .75) = -36 \n" ); document.write( "4x - 2x + 6 = -36 then simplify \n" ); document.write( "2x + 6 = -36 \n" ); document.write( "-6 on both sides \n" ); document.write( "2x = -42 \n" ); document.write( "divide by 2 on both sides \n" ); document.write( "x = -21\r \n" ); document.write( "\n" ); document.write( "Now place -21 in either equation and solve for y:\r \n" ); document.write( "\n" ); document.write( "2(-21) + 8y = 6 \n" ); document.write( "-42 + 8y = 6 \n" ); document.write( "+ 42 on both sides \n" ); document.write( "8y = 48 \n" ); document.write( "divide by 8 on both sides \n" ); document.write( "y = 6\r \n" ); document.write( "\n" ); document.write( "To check your work, put the values of x and y into either equation; \n" ); document.write( "2(-21) + 8(6) = 6 \n" ); document.write( "-42 + 48 = 6 \n" ); document.write( "6 = 6\r \n" ); document.write( "\n" ); document.write( "Your answer would be: \n" ); document.write( "(-21,6) \n" ); document.write( " |