document.write( "Question 263428: What is 8x+2y=-2, If y=5x+1?? \n" ); document.write( "
Algebra.Com's Answer #194135 by georgiabh(4)![]() ![]() ![]() You can put this solution on YOUR website! This is a simultaneous equation. \n" ); document.write( "We want to get an equation that has just x's or just y's so that it can be solved. You need to have a look at both equations to work out which would be the easiest way. \n" ); document.write( "In this case we are already told that y=5x+1 so all we have to do is substitute this into the equation. \n" ); document.write( "So 8x + 2y = -2 becomes 8x + 2(5x + 1) = -2 \n" ); document.write( "So, 8x + 10x + 2 = -2 \n" ); document.write( "18x + 2 = -2\r \n" ); document.write( "\n" ); document.write( "We now need to get x on one side of the equation and the number on the other. \n" ); document.write( "As in all equations we must do the same thing on both sides \n" ); document.write( "18x + 2 - 2 = -2 -2 \n" ); document.write( "18x = -4 \n" ); document.write( "x = -4/18 = -2/9\r \n" ); document.write( "\n" ); document.write( "We now put this value of x back into one of the equations to find y - look for which one looks the simplest. \n" ); document.write( "y = 5x+1 = -10/9 + 1 = -1/9\r \n" ); document.write( "\n" ); document.write( "So the answer is that x=-2/9 and y= -1/9 \n" ); document.write( " |