standard_description: Use variables to represent quantities in a real-world or mathematical problem, and construct simple equations and inequalities to solve problems by reasoning about the quantities.
problem_activity: Two expressions are given below.
Expression A:
$${5q-r}$$
Expression B:
$${ -2q+3r-4}$$
a.   Write a simplified expression that represents A + B.
b.   Write a simplified expression that represents A - B.


aligns: no