123456789
of 9

Solving Equations by Factoring

TRY IT:

Solve  x^2 + 8x + 12 = 0

Remember how I said that since there's an

x^2 ... we hope to get two answers?

Well, check out this guy:

Solve  x^2 + 4x + 4

Factor: ( x + 2 ) ( x + 2 ) = 0 ... Blobs = 0: x + 2 = 0 or x + 2 = 0 ... Solve: subtract 2 from both sides of both equations, which gives x = -2 or x = -2
Hey, we got the same guy twice!

Don't worry. These are just Gilligan's Island answers -- RERUNS!

So, the answer is just     { -2 }