What quadratic equation has - 4 and 2/3 as it's roots

3x^2 + 10x - 8 = 0.

Step-by-step explanation:

In factor form it would be:

(x + 4) (3x - 2) = 0 (because x + 4 = 0 gives x = - 4 and 3x - 2 = 0 gives x = 2/3);

Now change to standard form:

= 3x^2 - 2x + 12x - 8 = 0

= 3x^2 + 10x - 8 = 0.