# Area of Rectangles (Grade 3)

Videos, solutions and lessons to help Grade 3 students learn to relate area to the operations of multiplication and addition.

A. Find the area of a rectangle with whole-number side lengths by tiling it, and show that the area is the same as would be found by multiplying the side lengths.

B. Multiply side lengths to find areas of rectangles with whole-number side lengths in the context of solving real world and mathematical problems, and represent whole-number products as rectangular areas in mathematical reasoning.

C. Use tiling to show in a concrete case that the area of a rectangle with whole-number side lengths a and b + c is the sum of a × b and a × c. Use area models to represent the distributive property in mathematical reasoning.

D. Recognize area as additive. Find areas of rectilinear figures by decomposing them into non-overlapping rectangles and adding the areas of the non-overlapping parts, applying this technique to solve real world problems.

Common Core: 3.MD.7

### Suggested Learning Targets

• I can use tiles to find the area of rectangles.
• I can explain the relationship between tiling and multiplying side lengths to find the area of rectangles.
• I can multiply adjacent side lengths of rectangles to solve word problems.
• I can use area models to explain the distributive property.
• I can decompose an irregular figure into non-overlapping rectangles.
• I can explain area as additive and use this understanding to solve word problems.

Related Topics:

### A. Find the area of a rectangle with whole-number side lengths by tiling it, and show that the area is the same as would be found by multiplying the side lengths.

Relating area to multiplication and division (Common Core Standard 3.MD.7)
In this lesson you will learn to find the area of a rectangle by making a connection between area and arrays.
Find the area of a rectangle using arrays - 3.MD.7

Relate area to the operations of multiplication and addition.--Lesson 1 of 4 (Common Core 3.MD.7)
In this lesson you will learn how to find the area of a polygon by multiplying the length and the width.
3 MD 7
In this lesson, you will learn to explain the relationship between counting unit squares and multiplying side lengths to find the area of rectangles.

Find the area of a rectangle using side lengths - 3.MD.7
In this lesson, you will find areas of rectangles by multiplying whole number side lengths and mathematical reasoning.

### B. Multiply side lengths to find areas of rectangles with whole-number side lengths in the context of solving real world and mathematical problems, and represent whole-number products as rectangular areas in mathematical reasoning.

Relate area to the operations of multiplication and addition.--Lesson 2 of 4
In this lesson you will learn how to find area in real world situations by multiplying.
Example: Kyle wants to use 1 square foot pieces to carpet his bedroom floor. How many pieces of carpet will he need?

3 MD 7
In this lesson, you will learn to multiply side lengths to find the area of rectangles
Example: Drew wants to tile his bathroom with 1 foot tiles. How may tiles will he need?

### C. Use tiling to show in a concrete case that the area of a rectangle with whole-number side lengths a and b + c is the sum of a × b and a × c. Use area models to represent the distributive property in mathematical reasoning.

Apply the distributive property using area models - 3.MD.7
In this lesson, you will learn how to use the distributive property by using area models.

3 MD 7
In this lesson, you will learn how to area models to explain the distributive property.

### D. Recognize area as additive. Find areas of rectilinear figures by decomposing them into non-overlapping rectangles and adding the areas of the non-overlapping parts, applying this technique to solve real world problems.

Relate area to the operations of multiplication and addition.--Lesson 3 of 4
In this lesson you will learn how to find the area of a rectangle or square by breaking it into smaller rectangles.

Relate area to the operations of multiplication and addition.--Lesson 4 of 4
In this lesson you will learn how to find the area of a polygon by adding the area of smaller rectangles.
3 MD 7
In this lesson, you will learn how to decompose an irregular figure into non-overlapping rectangles to find the area.
3.md.7d
The Common Core State Standards (CCSS) videos are designed to support states, schools, and teachers in the implementation of the CCSS. Each video is an audiovisual resource that focuses on one or more specific standards and usually includes examples/illustrations geared to enhancing understanding. The intent of each content-focused video is to clarify the meaning of the individual standard rather than to be a guide on how to teach each standard although the examples can be adapted for instructional use.