How do you use the important points to sketch the graph of #5x^2 - 3x + 2#?

1 Answer
Sep 1, 2016

Find the points that are easy to find.

Explanation:

For #5x^2−3x+2 #, you should take the easiest point possible: the point where x=0. #5(0^2)-3(0)+2# is equal to 0-0+2=2. Thus we know that one point is #(0, 2)#.
Then we could plug in a small random number such as 2.
#5(2^2)-3(2)+2#
#5(4)-6+2#
#20-6+2#
That will equal 16. So we know another point on our graph is (2, 16).
But since this is a parabola that faces up, we need another point.
#5(-1^2)-3(-1)+2#
#5(1)+3+2#
Hence we can infer another point is (-1, 10)
graph{5x^2-3x+2 [-40, 40, -20, 20]}

With the 3 points we have, we can draw the graph with artistic flair now.