$y=x+3$y=x+3

$\displaystyle y= \frac{2}{3}x+ \frac{5}{3}$\displaystyle y= \frac{2}{3}x+ \frac{5}{3}

$y=x-3$y=x-3

$\displaystyle y= \frac{2}{3}x+ \frac{11}3{}$\displaystyle y= \frac{2}{3}x+ \frac{11}3{}