Answer:
Step-by-step explanation:
First off, <em>B</em> is zero, so there is no <em>phase shift</em>, meaning that the vertex stays on the y-axis. Next, <em>A</em> is negative, so the parabola opens down, and whenever you have a parabola opening down, it does so at maximum. Finally, <em>C</em> represents our y-intercept, or in this case, our <em>vertical shift</em>. Our y-intercept is (0, −1), and so as our vertex, hence our answer.
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