Question

Factor 2x^2-16x+14

In http://www.wolframalpha.com/input/?i=factor+2x%5E2-16x%2B14

It says 2(x-1)(x-7).
I plugged it into the quadratic formula and got x = 4 +/- 3
Where does the 2 come from?

Answer 1

2 is the common factor of 2, 16 and 14

Answer 2

2x^2-16x+14


2(x^2-8x+7)


So 2x^2-16x+14 = 0 and 2(x^2-8x+7) = 0 have the same solutions since the two expressions are equivalent, which means they share the same (basic) factorization. The only difference between the factorizations is that 2 on the outside.