Question

Solve the following equation. Show your work.

x^2 - 4 = 0.

Answer 1

Hint:
Difference of Squares Rule
\[\Large a^2-b^2 = (a-b)(a+b)\]

Answer 2

Sorry :( still lost

Answer 3

So for example, if a = x and b = 3, then
\[\Large a^2-b^2 = (a-b)(a+b)\]
\[\Large x^2-3^2 = (x-3)(x+3)\]
\[\Large x^2-9 = (x-3)(x+3)\]

Answer 4

What would \(\LARGE x^2-4\) factor to?

Answer 5

(x-2)(x+2)

Answer 6

yes, so if x^2 - 4 = 0,then either

x-2 = 0 or x+2 = 0

Answer 7

so you need to solve x-2 = 0 and x+2 = 0 to get the two solutions

Answer 8

sorry I skipped a step. I should have gone from x^2-4 = 0 to (x-2)(x+2) = 0 then break down to those two equations. But you get the idea hopefully

Answer 9

so it would be

x=2 and x=-2

Answer 10

correct

Answer 11

thank you a bunch!

Answer 12

Let's check each possible answer

To check x = 2, we replace each x with 2 to get
x^2-4 = 0
(2)^2-4 = 0
4-4 = 0
0 = 0

Similar work would be done to check x = -2

Answer 13

no problem