Consider the quadratic expression given below. factor the following expression completely. 3x^2-30x-72

Using cross multiplication method,

x                         -12       -12x

x                             2          2x  

                        -24        -10x

Therefore, 

                               =3(x-12)(x+2)

The factor form of the given expression is 3(x-12)(x+2).

Step-by-step explanation:

The given expression is

The middle term can be written as -12x+2x.

Therefore the factor form of the given expression is 3(x-12)(x+2).

U = {keys on a keyboard}, choice 1

We can rule out choice 2 since {4,9,?} are not letters.

We can rule out choice 3 since {x,y,?} are not numbers.

We can rule out choice 4 since {x,y,4,9} are not punctuation marks.