Linear and Quadratic Regression Using Desmos

After running a linear regression in desmos, this is what pops up. What is the slope?

• 1

• 0.039

• -0.171

After running a linear regression in desmos, this is what pops up. What is the correlation coefficient?

• 1

• 0.039

• -0.179

• 0.9846

Estimate the correlation coefficient for this scatterplot.

• A) r = 1.2

• B) r = 0.89

• C)r = 0

• D) r = -0.89

Describe the correlation:

r = -0.98

• Strong positive

• Weak positive

• Strong negative

• Weak negative

A restaurant sells pizza for the prices in the data table.  Calculate the linear regression equation of the data.

• y = 1.5x + 12
• y = 12x + 1.5
• y = 0.67x - 8
• y = -8x + 0.67

The linear regression equation is y = 61.93x - 1.79.  According to the model, the slope can be interpreted as:

• After 0 hours of driving, they went 61.93 miles.
• They drove at a speed of 61.93 miles per hour.
• They drove 61.93 miles total.
• They drove 61.93 hours total.

Data was collected on the weight of a male  laboratory rat for the first 25 weeks after its birth. The linear regression equation is 
y= 40x+100, where x is number of weeks and y is weight in grams. 
What does the y-intercept mean in context of the problem?

• The predicted weight of the rat in year 0. 
• The predicted weight of the rat at birth. 
• The current weight of the rat. 
• The average increase in the rat's weight. 

After running a regression and plotting the residuals in desmos, this pops up. Which ordered pair is the furthest from the line of best fit?

• (1 , .20)

• (3, .187)

• (5, .33)

• (7, .35)