0

Keeping the Equation Balanced: IM 8.4.2

IM 6 – 8 Math, GeoGebra Classroom Activities, Aug 10, 2020

“Keeping the Equation Balanced” from IM Grade 8 by Open Up Resources and Illustrative Mathematics. Licensed under the Creative Commons Attribution 4.0 license.

Lesson 8.4.2
1. IM 8.4.2 Lesson: Keeping the Equation Balanced
Practice 8.4.2
1. IM 8.4.2 Practice: Keeping the Equation Balanced

Information

1.1.

IM 8.4.2 Lesson: Keeping the Equation Balanced

What do you notice? What do you wonder?

This picture represents a hanger that is balanced because the weight on both sides is the same.

Elena takes two triangles off of the left side and three triangles off of the right side. Will the hanger still be in balance, or will it tip to one side? Which side?

Use the applet to see if your answer to the questions above were correct.

Explain how you know.

Can you find another way to make the hanger balance?

After you make a prediction, use the applet to see if you were right.

If a triangle weighs 1 gram, how much does a square weigh?

Try your own Hanger Balances!

Can you find another pair of values that makes the hanger balance?

A triangle weighs 3 grams, and a circle weighs 6 grams. Use this applet to help find the weight of a square.

The weight of a square:

Write an equation to represent this hanger.

Find the weight of a pentagon.

The weight of a pentagon:

Write an equation to represent this hanger.

0

Keeping the Equation Balanced: IM 8.4.2

Table of Contents

Information

1.

Lesson 8.4.2

1.1.

IM 8.4.2 Lesson: Keeping the Equation Balanced

What do you notice? What do you wonder?

This picture represents a hanger that is balanced because the weight on both sides is the same.

Use the applet to see if your answer to the questions above were correct.

After you make a prediction, use the applet to see if you were right.

Try your own Hanger Balances!

A triangle weighs 3 grams, and a circle weighs 6 grams. Use this applet to help find the weight of a square.

Find the weight of a pentagon.

Try your own!

2.

Practice 8.4.2

2.1.

IM 8.4.2 Practice: Keeping the Equation Balanced

Which of the changes would keep the hanger in balance?

Here is a balanced hanger diagram.

What is the weight of a square if a triangle weighs 4 grams?

Andre came up with the following puzzle. “I am three years younger than my brother, and I am 2 years older than my sister. My mom's age is one less than three times my brother's age. When you add all our ages, you get 87. What are our ages?”

These two lines are parallel. Write an equation for each.