Question

Simplify.
(x – 3)(x2 – 4x – 7)

A.
x3 – 3x2 + 12x + 21

B.
x3 – 7x2 + 19x + 21

C.
x3 – 7x2 + 5x + 21

D.
x3 + x2 – 5x – 21

Answer 1

(x−3)((x(2)−4x)−7)
=(x+(−3))(x(2)+(−4x)+(−7))
=(x)(x(2))+(x)(−4x)+(x)(−7)+(−3)(x(2))+(−3)(−4x)+(−3)(−7)
=2x2−4x2−7x−6x+12x+21
=−2x2−x+21

Answer 2

Now let's go down further:

Answer 3

a?

Answer 4

((−2)(x)(2)−x)+21
=(−2)(x)(2)+(−x)+21
=(−5x)+21
=−5x+21

Answer 5

Might be C

Answer 6

alright thanks!

Answer 7

Not only does @Saphira_Shapiro do the work for you, she gets the answer wrong. Maybe you ought to learn how to do it yourself :-)

the x2 represents x*x or x^2, not x(2) or x*2
the x3 represents x*x*x or x^3, not x(3) or x*3

Answer 8

@whpalmer4 If you have a problem, keep it to yourself. I learn how to solve that way. I am sorry you don't.

Answer 9

I may not be Einstein but sometimes I get them correct too.

Answer 10

Again, see the Code of Conduct: "Give Help, Not Answers"

Answer 11

I have the same problem can someone help me understand it? and answer it?