How do you factor #(r+s)(s+t)-(r+s)(s-t)+(r+s)(s+t)#?
To factor this expression, look for a factor that all the terms have in common.
Then you can factor that one out from all the terms.
In this case, all three terms have a factor in common, namely
• Be sure to keep the parentheses for the expression you factored out
It's an error to write it like this (without the beginning parentheses)
This means that only the
• Be sure to enclose the expression in brackets
It's an error to write it like this (without the brackets)
This doesn't show that
To check factoring, see if distributing the factor brings back the original expression
#"take out the "color(blue)"common factor "(r+s)#
#"simplifying the terms in the bracket gives"#