# Plz Check

#### Dominic

##### Junior Member
Evaluate: (g - 6h)(g + 6h)

(g)(g) + (g)(h) + (-6h)(g) + (-6h)(6h)

g^2 + gh + (-6gh) + (-36h^2)

g^2 - 30 g^2h^4 <-- answer

Is this right?

#### Matt

##### Junior Member
Hi Dominic,

Dominic said:
Evaluate: (g - 6h)(g + 6h)

(g)(g) + (g)(h) + (-6h)(g) + (-6h)(6h)

g^2 + gh + (-6gh) + (-36h^2) stop right here
It looks like you are using FOIL. That last line should actually be:

. . . . g<sup>2</sup> + 6gh + (-6gh) + (-36h<sup>2</sup>)

which makes the final answer:

. . . . g<sup>2</sup> -36h<sup>2</sup>

#### Denis

##### Senior Member
"Evaluate: (g - 6h)(g + 6h)
(g)(g) + (g)(h) + (-6h)(g) + (-6h)(6h)
g^2 + gh + (-6gh) + (-36h^2) stop right here"

Actually, "stop" a line earlier!
Your 2nd term should be (g)(6h): that's your only error...

thanks

G

#### Guest

##### Guest
It seems like some information is missing or the problem was not asked correctly (possibly by a textbook). "g<sup>2</sup> - 36h<sup>2</sup>" is not evaluated. When you evaluate something, you end up with a number, not an expression with variables. Perhaps the instructions meant to be "simplify" or "expand".

#### ~Midnight.Kitten~

##### Junior Member
so would tyou add the oppoisite to 6 which would be -6 ? as a step to the answer?

#### Gene

##### Senior Member
Ashley, Matt has it correct. I don't follow your "add the opposite of 6"
Everyone should notice that the original problem is in the form
(a+b)(a-b) which always gives a^2-b^2