For me the easiest way would be to change to slope formula, y=Mx+b where m is the slope and b is the y-intercept. So first you want to get y by itself so I subtract 10 and subtract 2x to get 5y=-2x+10. Then divide by 5 to get y=-2/5x + 10. Start the graph by plotting the point (0,10) and then from there, use the slope of negative two fifths. Remember rise over run!