to find the intercepts, that is where the graph crosses the x and y axes
• let x = 0, in the equation for y- intercept
• let y = 0, in the equation for x- intercept
x = 0 : 0 - 2y = - 6 ⇔ y = 3 ← y- intercept → (0, - 3)
y = 0 : 2x - 0 = - 6 ⇒ x = - 3 ← x- intercept → (- 3, 0 )
