Question

Based on the graph of y = x2 − 2x − 3, what is the x coordinate of the positive x-intercept?

Answer 1

The x intercept is found by letting y = 0 so why don't you replace y with 0, factor and solve and pick the positive answer.

Answer 2

Factor the quadratic to get the roots.

y = (x - 3)(x + 1) --> x-intercepts are: x = 3, x = -1.

x = 3 is the only positive x-intercept. Therefore, the co-ordinate (3, 0) is the co-ordinate of the positive x-intercept.