Question

(a + b - c)(a + b + c)
I'm getting a^2+b^2-c^2+2bc but this isn't right. Little help?

Answer 1

Use the distributive property.

Answer 2

$$\Huge a(b+c)=ab+ac$$

Answer 3

I would group \(a+b\) together and use \((\alpha+\beta)(\alpha-\beta)=\alpha^2-\beta^2\) :)

Answer 4

$$(a + b - c)(a + b + c) $$
$$ =(a + b - c)a + (a + b - c)b + (a + b - c)c$$

Answer 5

Now use this form of the distributive property:$$\Huge (b+c)a=ba+ca$$

Answer 6

@skullpatrol I think kc-kennylau gave us the easiest way.

Answer 7

Let the student decide please :-)

Answer 8

I am sorry.

Answer 9

np

Answer 10

Figured it out! thanks a bunch for your help (:

Answer 11

Took me a few minutes but i got it! :)

Answer 12

Thanks for trying to understand :)

Answer 13

Thank-you for your time!

Answer 14

:-)