Writing equations for trend lines

Front

What is a trend line?

Back

A trend line is a straight line that best represents the data on a scatter plot, showing the general direction of the data points.

Front

How do you write an equation for a trend line?

Back

An equation for a trend line is typically written in the form y = mx + b, where m is the slope and b is the y-intercept.

Front

What does the slope (m) represent in a trend line equation?

Back

The slope (m) represents the rate of change between the two variables in the scatter plot.

Front

What does the y-intercept (b) represent in a trend line equation?

Back

The y-intercept (b) is the value of y when x is 0, indicating where the trend line crosses the y-axis.

Front

If a trend line has a slope of 2.5, what does this indicate?

Back

A slope of 2.5 indicates that for every 1 unit increase in x, y increases by 2.5 units.

Front

What is the purpose of using a trend line in data analysis?

Back

The purpose of using a trend line is to make predictions about future data points based on the existing data.

Front

How can you use a trend line to make predictions?

Back

You can use the equation of the trend line to substitute values of x to find corresponding values of y.

Front

What is the significance of a positive slope in a trend line?

Back

A positive slope indicates a direct relationship between the two variables, meaning as one increases, the other also increases.

Front

What is the significance of a negative slope in a trend line?

Back

A negative slope indicates an inverse relationship between the two variables, meaning as one increases, the other decreases.

Front

How do you determine the best fit line for a scatter plot?

Back

The best fit line is determined by minimizing the distance between the line and all the data points, often using methods like least squares.