Interpreting Lines:

Introduction to Slope

Graphs help us recognize patterns in data and are useful in almost every industry. You will also be using graphs in your team project this week.

Slope = The rate of change of a function on a graph, the steepness of the line

Video Source (03:30 mins) | Transcript

To determine if the slope is positive or negative: Follow the line from left to right. If the graph goes up, its slope is positive. If the graph goes down, its slope is negative.

Additional Resources

Khan Academy: Intro to Slope (06:55 mins; Transcript)
Khan Academy: Positive and Negative Slope (05:01 mins; Transcript)

Practice Problems

Use the graph below to answer questions 1 through 5.

This is an image of a graph with five different lines. Line A starts in the top left and ends in the bottom right. Line B starts in the bottom left and ends in the top right. Line C starts in the top left and ends in the bottom right. Line D starts around the lower middle area of the left side and ends in the upper middle area of the right side. Line E starts around the x axis on the left and ends 4 units down from the x axis on the right.

Is the slope of line A positive or negative?
1. Positive
2. Negative
Is the slope of line B positive or negative?
1. Positive
2. Negative
Is the slope of line C positive or negative?
1. Positive
2. Negative
Is the slope of line D positive or negative?
1. Positive
2. Negative
Is the slope of line E positive or negative?
1. Positive
2. Negative

Solutions

Negative (Written Solution)

When you follow line A from left to right, the line goes down. So the slope is negative.
Positive (Written Solution)

When you follow line B from left to right it goes up, so the slope is positive.
Negative
Positive
Negative