TEKS 2.7C: Solve for the Unknown
Represent and Solve for the Unknown
About this lesson
Learning Target: I can solve addition and subtraction equations with a missing number and explain how I know.
Focuses On:
- Solving for an unknown in the equation
- Using inverse operations for problem solving
Builds On:
1.3F:
Generate and solve problem situations when given a number sentence involving addition or subtraction of numbers within 20 (R)
Next Level:
3.5A:
Represent and solve one- and two-step problems involving addition and subtraction of whole numbers to 1,000 using pictorial models, number lines, and equations
Read More:
This lesson is designed to support student understanding of solving for an unknown in an addition or subtraction equation.
The two instructional blocks in this lesson focus on solving for the unknown in an equation and using inverse operations to solve for the unknown.
In the first instructional block, students look at addition and subtraction equations with a part missing and try to identify what value will make the equation true.
The second instructional block focuses on using the strategy of inverse operations to figure out the unknown. This strategy will help students be more efficient versus using a strategy like guess and check or counting up.
Scaffolds and supports such as pictorial representations and models are intentionally built throughout the lesson to support conceptual learning.
Grade 2MathTEKS 2.7C