Question

How do you graph `y=-2x^2`?

Answer 1

Calculate several points on the curve and connect the points with a smooth line. In general the more points you use, the more accurate your graph's line will be.

Explanation:

For the equation `y = -2x^2`
we could calculate values of `y` for a collection of `x` values:
`color(white)("XXXX")` `{:(x, ,y), graph{-2x^2 [-3.91, 3.882, -3.695, 0.202]} (0,,0), (+1,,-2), (-1,,-2), (+2,,-8), (-2,,-8) :}`