Problem 1.1 - Launch Video

**Focus Question:** How can you find the total value of a combination of positive and negative numbers?

Problem 1.2

**Focus Question:** How can you use the number line to compare two numbers?

Problem 1.3 - Launch Video

**Focus Question:** How can you write a number sentence to represent a change on a number line, and how can you use a number line to represent a number sentence?

Problem 1.4

**Focus Question:** How can you use a chip model to represent addition and subtraction?

**In this investigation, we will be using chips to represent positive and negative integers. **

You may have heard the terms, "In the red" (meaning you owe or have a negative amount of money) and "In the black"(meaning have a positive amount of money)

In the image above, there are black positive chips and red negative chips on the board. Some red and black chips have already been put together in "zero pairs" that cancel each other out. Is this image "in the black" or "In the red"? How do you know?

**Now try for yourself: **

Problem 2.1 - Launch Video

**Focus Question:** How can you predict whether the result of an addition of two numbers will be positive, negative, or zero?

Online Help Math is Fun Site:

Adding and Subtracting Negative Numbers

Problem 2.2

**Focus Question:** How is a chip model or number line useful in determining an algorithm for subtraction?

Problem 2.3

**Focus Question:** How are the algorithms for addition and subtraction of integers related?

Problem 2.4 - Launch Video

**Focus Question:** What related sentence is equivalent to 4 + n = 43 and makes it easier to find the value of n?