Question
The vertex of a parabola is(-2,-4). One x-intercept is 7. What is the other x-intercept?
Answers
Reiny
We can find this without knowing the equation, by using the property that the x of the vertex is midway between the x interxepts
so let the other one be a
then (a + 7)/2 = -2
a+7 = -4
a = -11
the other one is -11
so let the other one be a
then (a + 7)/2 = -2
a+7 = -4
a = -11
the other one is -11