Question

How do you solve `-20x^2 + 320 = 0`?

Answer 1

`x=color(blue)(+4 , -4`

Explanation:

`-20x^2 = -320`

`20x^2 = 320`

`x^2 = 320/20`

`x^2 = 16`

`x=sqrt16`

`x=color(blue)(+-4`