Question

Simplify.
(x – 5)(x2 – 2x – 6)

A.
x3 + x2 – 4x + 30

B.
x3 – 5x2 + 10x + 30

C.
x3 – 7x2 + 16x + 30

D.
x3 – 7x2 + 4x + 30

Answer 1

Is it 2x or x2?

Answer 2

x^2

Answer 3

A hint: this expression can be written as x(x2-2x-6) - 5(x2-2x-6)

Answer 4

its going to take a bit of work
but
just multiply it out

Answer 5

so you mean \[(x-5)(x ^{2}-2x-6)\] is this right?

Answer 6

Yes

Answer 7

watch for the switch of signs of - and +

Answer 8

I got A but this is still confusing me..

Answer 9

\[x ^{3}-2x ^{2}-6x-5x ^{2}+10x+30\]
\[x ^{3}-2x ^{2}-5x ^{2}-6x+10x+30\]
\[x ^{3}-7x ^{2}+4x+30\]

Answer 10

I think its D not A

Answer 11

this also requires laws of exponents

Answer 12

I got A

Answer 13

it is D

Answer 14

thanks for the medal @texaschic101

Answer 15

you worked out the problem correctly. I give credit where credit is due :)

Answer 16

Thank you so much!

Answer 17

THIS IS AN EXAMPLE

(x – 2) (x^2 – 3x – 4)
i will multiply with teh x first
x ( x^2 – 2x – 4)
x ^3 - 2x - 4
^ nothing else happens
added

i multiply with the -2
-2 (x^2 – 3x – 4)
-2x^2 + 6x + 8
^ L____L_____switch of signs and multiply of coefficients
no adding of exponent, multiplying of coefficient


get both results
add like terms
x ^3 - 2x - 4
-2x^2 + 6x + 8
------------------
x^3 - 2^2 + 4x + 4

this should be correct