SOLUTION: Find the x-intercepts and y-intercept of y = -x^2 + 3x + 4. Sketch the curve, using the x-intercepts and y-intercept to help you.

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Question 749770: Find the x-intercepts and y-intercept of y = -x^2 + 3x + 4. Sketch the curve, using the x-intercepts and y-intercept to help you.
Answer by josgarithmetic(39613) About Me  (Show Source):
You can put this solution on YOUR website!
Find y intercept using x=0. y=-0%5E2%2B3%2A0%2B4=4, so you have (0,4).

y=%28x+-4%29%28-x+-1%29 is the factored form of the given function which you can also rewrite as:
highlight%28y=-1%2A%28x-4%29%28x%2B1%29%29.
The value of y will be 0 when x=4 or when x=-1.
The x intercepts are then (-1,0) and (4,0). Note also, the maximum point occurs at x=1.5, the parabola opens downward.

Compare that information to the graph:
graph%28300%2C300%2C-7%2C7%2C-7%2C7%2C-x%5E2%2B3x%2B4%29