Understanding Linear Equations from Graphs

This video tutorial explains how to find linear equations from graphs. It covers the concepts of slope and y-intercept, demonstrating how to calculate them using two examples. The slope is described as rise over run, and the y-intercept is identified as the point where the line crosses the y-axis. The video also provides guidance on writing the equation in the form y = mx + b, emphasizing the importance of simplifying the equation for clarity.

What two key pieces of information are needed to find a linear equation from a graph?

• Rise and run

• Slope and x-intercept

• Slope and y-intercept

• X-intercept and y-intercept

How is the slope of a line typically defined?

• Run over rise

• X-intercept over y-intercept

• Rise over run

• Y-intercept over x-intercept

In the first example, what is the calculated slope of the line?

• 4

• 3

• 1

• 0

What is the y-intercept of the line in the first graph?

• 3

• 0

• 1

• 4

What is the equation of the line from the first graph?

• y = x - 4

• y = 4x + 1

• y = 3x + 4

• y = x + 4

In the second example, what is the calculated slope of the line?

• 2/5

• -2/5

• 1/5

• -1/5

What is the y-intercept of the line in the second graph?

• -1

• -3

• 3

• 1

What is the equation of the line from the second graph?

• y = -1/5x + 3

• y = 1/5x + 3

• y = -1/5x - 3

• y = 1/5x - 3

Why is it often preferred to write the equation without the coefficient of 1?

• It is required by all teachers

• It is mathematically incorrect

• It is a stylistic preference

• It makes the equation longer

What is the common way to express a negative y-intercept in an equation?

• Using a plus sign

• Using a division sign

• Using a minus sign

• Using a multiplication sign