Hi

Just wandering

When I factorise the following :

4s-16t+20r

It will equal to 2 ( 2s - 8t + 10 r )
This was the answer in the book

However , I managed to factorise it to become :

4 ( s-4t+5r)

is this correct ? Because when you multiple it out , it gives you the same anwer which is 4s-16t-20r

Also , another one was :

56x^2y - 28 xy^2

In the book the anwer gave me : 7xy ( 8x - 4y)

I got 28xy ( 2y - y)

Is this the same ?

If not .. why ?

1 answer

You are correct on both counts, the book is in error.