You can put this solution on YOUR website! 4X+Y=7 OR Y=-4X+7 (red line) THIS IS A LINE EQUATION WITH A SLOPE=-4 & A Y INTERCEPT=7.
Y=X+6 (green line) HERE YOU HAVE A LINE WITH A SLOPE=12 & A Y INTERCEPT=6 (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, of TWO functions -4x +7 and x +6).