Suppose a parabola has its vertex at (0, 1) and its zeros at x = -2 and x = 2. Then equals _____.
A. 1-1/4x^2
B. 4-x^2
C. X^2-1
D. X^2-4
2 answers
The vertex is at (0,4) sorry, I copied it wrong.
since the vertex is above the x-axis, we will have (with a > 0)
y = -a(x-h)^2 + k
We know (h,k) = (0,4), so
y = -ax^2 + 4
Since y(2) = 0, 0=-4a+4, so a=1
y = -x^2 + 4, so (B)
y = -a(x-h)^2 + k
We know (h,k) = (0,4), so
y = -ax^2 + 4
Since y(2) = 0, 0=-4a+4, so a=1
y = -x^2 + 4, so (B)