Understanding Slope and Trend Lines Quiz

The graph shows a trend line y=1/4x. The grade of a hill is its steepness represented as a percent. Jin tracks his walking speed up different hills. What does the rate of change, or slope, represent?

• Increase in walking speed of 1 mph for each increase of 1% in the grade of the hill.

• Decrease in walking speed of 1 mph for each increase of 1% in the grade of the hill.

• Increase in walking speed of 1/4 mph for each increase of 1% in the grade of the hill.

• Decrease in walking speed of 1/4 mph for each increase of 1% in the grade of the hill.

Which trend line is the best model of the data?

line A diagonal from the dots, line B is in the middle of the dots, line C on the line for a portion of the dots.

• Line A is the best model of the data.

• Line B is the best model of the data.

• Line C is the best model of the data.

• All three lines equally model the data.

What are the slope and y-intercept of the line?

In the picture the trend line equation is y=1.33x+2

• The slope is 3 and the y-intercept is 2.

• The slope is 1.33 and the y-intercept is 2.

• The slope is 2 and the y-intercept is 3.

• The slope is 2 and the y-intercept is 1.33.

Draw a trend line in the scatter plot.

The trend line is in the middle of the dots. the line is decreasing.

• A line with a negative slope.

• A horizontal line across the scatter plot.

• A vertical line through the scatter plot.

The scatter plot shows the time spent studying compared to test scores for Mr. Stone’s eighth-grade class. What does the y-intercept represent?

In the picture graph shows time spent studying x and test score y. the trend line equation is y=4.5+48. It has a positive association. the y-intercept is (0,50).

• The test score when studying 0 hours.

• The test score when studying 50 hours.

• The test score when studying 10 hours.

• The test score when studying 5 hours.