How do you graph y equals negative2x2 plus 5?

Answer 1

the quadratical functions 's form is :

y=ax2 +bx+c

first you have to find (-b/2a) and get its value .

Draw the graph and try random 2 other values for x (I prefer you try one greater than -b/2a and other less one )

then connect between the points with a curvy line :)

y = 2x2 + 5

First, the parabola opens upward (a > 0), the axis of symmetry is the y-axis (b = 0), the y-intercept is 5 (c = 5), vertex is (0, 5) since it lies on the axis of symmetry, and there are not x-intercepts (ac > b2) .

So that you need to find just one point which will give you its symmetric point.

Let x = 1, y = 7; (1, 7) its symmetric point is (-1, -7).

Plot (0, 5), (-1, -7), (1, 7), then draw a smooth curve that passes through these points.