Lesson 4.10:
Algebra-Write Equations to Represent Addition: How do you write a number sentence to represent a problem?
2.OA.1 Use addition and subtraction within 100 to solve one- and two-step word problems involving situations of adding to, taking from, putting together, taking apart, and comparing, with unknowns in all positions, e.g., by using drawings and equations with a symbol for the unknown number to represent the problem.