y = x² - 2x - 3
a) Equate the equation to 0 ⇒ y = 0
x² - 2x - 3 = 0
b) Solve for the roots (x values) by factoring the quadratic equation:
Factors:
(x - 3) (x + 1) = 0
x - 3 = 0 x + 1 = 0
x - 3 + 3 = 0 + 3 x + 1 - 1 = 0 - 1
x = 3 x = -1
ANSWERS:
1.) The value of y is 0 (zero) at x-axis values 3 and -1.
2) The graph, which is a parabola opening upwards (with vertex at minimum), intersects the x-axis at 3 and -1.