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1 vote
Factor x^2 - 4x + 5.

Prime
(x + 5)(x - 1)
(X - 5)(x - 1)
(x + 5)(x + 1)

User HMD
by
5.3k points

1 Answer

2 votes

Answer:

Uhh? You can't factor this!

Explanation:

So.. we see that the last term, the constant, (the +5) is positive, which means the two terms (the a and b on the (x+a)(x+b) must be either both positive or both negative).

We try positive, and we end up with

(x+1)(x+5)

x^2 + x + 5x + 5

x^2 + 6x + 5

which is not what we want!

We try negative, and we end up with

(x-1)(x-5)

x^2 -x -5x +5

x^2 -6x +5

which is also not what we want!

This isn't factorable!

You can always complete the square or utilize the quadratic equation, but you can't factor it.

User Overlord
by
5.7k points