Which of the following is the complete factorization of 10x - 3 - 3x 2?

(3x - 1) (x + 3) ?

- (3x + 1) (x - 3) ?

- (3x - 1) (x - 3) ?

-3x^2+10x-3

This is of the form ax^2+bx+c. We need to find two values, j and k, such that:

jk=ac=9 and j+k=b=10, so j and k must be 1 and 9.

Now replace bx with jx and kx in the original equation ...

-3x^2+x+9x-3 now factor 1st and 2nd pair of terms

-x (3x-1) + 3 (3x-1)

(-x+3) (3x-1) or equivalently ...

- (x-3) (3x-1) or as they put it:

- (3x-1) (x-3)