Step-by-step explanation:
Using vertex form of a parabola:
y = a (x − h)² + k
where (h, k) is the vertex.
If we say the vertex is (0, 80), then:
y = a (x − 0)² + 80
y = ax² + 80
The roots of the parabola are (-60, 0) and (60, 0). If we plug this in:
0 = a (60)² + 80
-80 = 3600a
a = -1/45
Noemi's team's answer is incorrect.
