Question

How do you factor `y= x^2-6x+5` ?

Answer 1

Factors are `y=(x-1)(x-5)`

Explanation:

If you have a quadratic function `ax^2+bx+c`, to factorise it you should identify two numbers whose product is `ac` and sum is `b`.

Here in `y=x^2-6x+5`, we should identify two numbers whose product is `5` and sum is `-6`.

Such numbers are `-5` and `-1` and now splitting middle term into these we get `y=x^2-5x-x+5` or

`y=x(x-5)-1(x-5)=(x-1)(x-5)`.