0
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.
Still curious? Ask our experts.
Chat with our AI personalities
Rafa
Fran
SteveAdd your answer:
Earn +20 pts
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.
