Question

If (x+5)^2=0, what is the value of (x-1)(x+1)?

Answer 1

(x+5)^2=0 --> Look at (x+5). What value of x makes x + 5 = 0?

---------
@william0123

Answer 2

-5

Answer 3

I messed that up. Just a second.

Answer 4

Let's knock this out. Cool. -5 it is.

Now, look at this: (x-1)(x+1)

If x = -5, then what is the value of (x - 1)(x-1)?
Hint: ( -5 - 1) * (-5 +1)

Take a guess and post.

Answer 5

What is this equal to: ( -5 - 1)
We'll do this by parts.

Answer 6

Is it 24?

Answer 7

altogether

Answer 8

Correct!

( -5 - 1) * (-5 +1)
= (-6)*(-4) = 24. Yes, you are correct.
Hey, you could multiply (x-1)(x+1) to get x^2 -1 and then substitute -5 and get the same result.

Answer 9

@Directrix Thanks :)

Answer 10

Glad to help. I enjoyed it.