Answer:
m = +/- 12
Step-by-step explanation:
A quadratic function has only one x-intercept when the discriminant is equal to 0. The discriminant is b^2 - 4(a)(c).
When we plug in what we know, we have:
m^2 - 4(18)(2) = 0.
Then using algebraic properties, solve for m.
m^2 - 144 = 0
m^2 = 144
m = +/- 12
When you plug in positive or negative 12, and then factor you will see that it comes out to a difference of squares, proving that there is only one x-intercept.
