test the value (x,y) of each point in the equation-y^2 + x <= -4 BY
1) because the equation has = so every point in the equation -y^2 + x = -4 is applied .... this case is B ... satisfy 2) A, E is in the same area choose one to test test A(-4,2) : -(2)^2 + (-4) <= -4 which is true the A and E is satisfy the inequality 3) no need to test fo C, D, F on the different area they are not satisfy. but you can guess it will satisfy -y^2 + x > -4
