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There are two (main) ways to graph this parabola.
The first is to simply substitute in values of x, find the corresponding y values and then plot those points and connect the points with a curve.
The second way is to 'complete the square' so that we can find where the maximum or minimum occurs and the y-intercept and graph from those two points. This is the process described below.
y = -x2 + 8x + 5
y = -(x2 - 8x) + 5
y = -(x2 - 8x + 16 - 16) + 5
y = -(x2 - 8x + 16) + 16 + 5
y = -(x-4)2 + 21
From this we can see that a maximum occurs at (4,21). To find the y-intercept, substitute in x=0, giving y=5.
From these two points, we get a pretty good idea of what the graph looks like. If you want more accuracy, substitute in more values of x.
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How do you graph a parabola?
y=x2+4x+1
How do you graph y equals x2?
The graph is a parabola facing (opening) upwards with the vertex at the origin.
What is the vertex of the parabola y equals x2 plus 8x plus 5?
The vertex has a minimum value of (-4, -11)
Is y equals x2 a function?
Y=X^2 is a function for it forms a parabola on a graph.
What is graph of the function y equals X2?
It looks like a parabola which looks like a U shape.
