SOLUTION: The graph of y = 5 + 9x − 2x^2
1. opens downwards and has vertex 2(1/4), 15(1/8)
2. opens upwards and has vertex 2(1/4), −15 (1/8)
3. opens downwards and has vertex −2(1
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-> SOLUTION: The graph of y = 5 + 9x − 2x^2
1. opens downwards and has vertex 2(1/4), 15(1/8)
2. opens upwards and has vertex 2(1/4), −15 (1/8)
3. opens downwards and has vertex −2(1
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Question 1142378: The graph of y = 5 + 9x − 2x^2
1. opens downwards and has vertex 2(1/4), 15(1/8)
2. opens upwards and has vertex 2(1/4), −15 (1/8)
3. opens downwards and has vertex −2(1/4), 15 (1/8)
4. opens upwards and has vertex −2(1/4), −15(1/8)
5. opens downwards and has vertex −2(1/4), −15(1/8) Answer by ikleyn(52884) (Show Source):
Since the coefficient at x^2 is negative (its value is -2), the graph opens downwards.
The x- coordinate of the vertex is x= (referring to the standard form of the quadratic function y = ax^2 + bx + c,
in which a= -2, b= 9).
Thus the x- coordinate of the vertex is x= = = in this case.
Among the given 5 optional answers, only n1 satisfies these conditions -- so, only n1 is the potential candidate.
Now substitute x= into the formula of the parabola to verify that y then equals .
Do this last check on your own.
