Last answer for the first question and in not sure about the second one
(2m + 7) - (3 - 4m)
First distribute the (-) in front of the quantity of 3 - 4m.
Think of it as this:
-1(3 - 4m)
You multiply each number inside the parenthesis by -1.
So:
3*-1 = -3
-4m * -1 = 4m
Now that you've distributed the negative you can remove the parenthesis.
Now you'll just set it all up like you would any normal problem. Because -3 is negative you'll make it subtract.... I'll show you what I mean:
2m + 7 - 3 + 4m
Combine like terms (Terms which have the same variables... in this case the same number of m's)
Rearranging them can help!
4m + 2m + 7 - 3
6m + 7 - 3
6m + 4, is our difference!
