# Lesson 8

Speaking of Scaling

### Lesson Narrative

In this lesson, students apply their knowledge of the relationships between original and scaled figures. Students decide what information is necessary to move backwards and forwards between lengths, surface areas, and volumes of an original solid and its dilation. They communicate with each other to obtain the data they need to solve a problem. Then, in an optional activity, they create a mathematical model of a real-world situation.

As students persist in asking their peers for information, they are making sense of a problem (MP1).

### Learning Goals

Teacher Facing

• Coordinate scale factors for lengths, surface areas, and volumes.

### Student Facing

• Let’s practice moving back and forth between scale factors for lengths, surface areas, and volumes.

### Required Preparation

Optionally, obtain several cylindrical beverage cans of different shapes and sizes.

### Student Facing

• I can calculate scale factors for lengths, surface areas, and volumes if I’m given any 1 of the 3 factors.

Building Towards

### Glossary Entries

• cube root

The cube root of a number $$x$$, written $$\sqrt{x}$$, is the number $$y$$ whose cube is $$x$$. That is, $$y^3 = x$$.

### Print Formatted Materials

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