Question

How do you factor `xy -x + 5y -5` by grouping?

Answer 1

`(y-1)(x+5)`

Explanation:

Group the terms in 'pairs' as follows.

`[xy-x]+[5y-5]`

now factorise each pair.

`color(red)(x)(y-1)+color(red)(5)(y-1)`

take out the `color(blue)"common factor"` (y -1)

`(y-1)(color(red)(x+5))=(y-1)(x+5)`