-8(1+5m)
First multiply the -8 on the outside by the first term inside the parentheses.
That gives -8 times 1, which is -8.
So write that down:
-8
Then multiply the 8 on the outside by the SECOND term inside the parentheses.
That give -8 times +5m, which is -40m.
So write that down next to the -8
-8-40m
When distributing, always be sure to take the signs of both what you're
multiplying along with what you're multiplying it by. That's extremely
important, and easy to miss if you aren't very careful.
Edwin
