The A value of a function in the form f of x is equal to a x squared plus b x plus c is negative. Which statement must be true?

The coefficient a determines whether the parabola opens up or down. Since a is negative, the parabola opens downward, so its vertex is a maximum. The other statements are not guaranteed because the y-intercept, axis of symmetry, and x-intercepts also depend on b and c.

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