Question

x2 - 4 = 0



x = 2; x = -2
x = 2
no solutions
x = -2

Answer 1

Factor the left side of the equation as (x+2)(x-2).

If (x+2)(x-2)=0, then one or both of the factors must be equal 0.

Therefore, x must be -2 or 2.

Answer 2

Lisa has three hog panels. Panel A is 8 feet long, panel B is 3 feet long, and panel C is 7 feet long. If the full length of each panel is used, can she build a triangular pen to hold her pet pig?


No, 8 - 7 < 3
Yes, 3 + 7 > 8
No, 3 + 7 < 8
Yes, 8 - 3 > 7

Answer 3

Why bother factoring? That is equivalent with \[x^2=4\]which immediately and apparently has solutions of \[x _{1,2}=\pm2\]