9514 1404 393
Answer:
0
Explanation:
When two points on a parabola have the same y-value, the line of symmetry is halfway between them. The vertex is on the line of symmetry. Its x-coordinate is ...
(-4 +4)/2 = 0
The x-coordinate of the vertex is 0.
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The graph shows 3 different parabolas with those x-intercepts. They all have vertices with an x-coordinate of 0.