Let $r$ and $s$ be the roots of $3x^2 + 4x + 12 = 0.$ Find $r^2 + s^2.$

My question here is that i go in an endless loop of substitution while using Vieta's formula. I want to keep using the Vieta formula so i can better understand it.

ive currently gotten this:

r + s = -4/3

rs = 4

but now im lost and dont know what to do.

im not asking for the answer, i would like a hint as to how to solve this by myself

Guest Dec 8, 2020