Linear Function in Context

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

• After 0 hours of driving, they went -1.79 miles.

• They are driving -1.79 miles per hour.

• They drove 1.79 miles total.

• They drive 1.79 hours total.

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.

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

Which is the best description of the y - intercept for the linear regression equation of the rats: Weight = 100 + 40(Time)?

• The y-intercept is 100, which means the rat is predicted to weigh 100 grams at birth. 

• The y-intercept is 100, which is where the graph crosses the y-axis. 

• 100 is where the data starts on the y-axis. 

• The y-intercept is 100, which means at a weight of 0, the rat will take 100 seconds.

Some data were collected on the weight of a male white laboratory rat for the first 25 weeks after its birth. The linear regression equation is:
Weight = 100 + 40(Time).
Which is the best description of the slope for this regression equation in context of the problem?

• The slope of the line of regression is the time since birth of the rate. It demonstrates the predicted weight of a laboratory rate after so many months since birth.

• The slope is 40 grams/week which means the mouse gains about 40 grams per week after birth.

• The slope is 40 and it means for every increase in weeks the graph will increase. 

• The slope is 40, which tells us the line increases. 

Roberto deposits the same amount of money each month into a checking account. Use the table to write an equation to model his balance, B, after m months.

• B = 200 + 55m

• B = 200 - 55m

• B = 200m + 55

• B = 200m - 55

Let f be the function that assigns to a temperature in degrees Celsius its equivalent in degrees Fahrenheit. The freezing point of water in degrees Celsius is zero while in degrees Fahrenheit it is 32. The boiling point of water is 100 degrees Celsius and 212 degrees Fahrenheit. Given that the function f is linear, use this information to find an equation for f.

• f = (9/5)C + 32

• f = (9/5)C - 32

• f = (9/5) + 32 C

• f = (9/5) - 32C

Moche started a summer business of mowing lawns. However, before he could mow lawns, he needed to purchase supplies (a lawnmower among other needs). Moche spent $395 gathering necessary materials. He makes on average $60 per lawn, mowed. Write an equation to show Moche his earnings for L lawns mowed.

• m = 60L - 395

• m = 60L + 395

• m = 60 - 395L

• m = 60 + 395L

Charlie rented a moving truck. He paid a daily fee plus a per-mile fee to rent the truck. The equation below represents the daily amount Charlie paid for the truck if he drives it x miles.
y=0.5x+10
What does the slope of the graph of this equation represent?

• The daily fee for the moving truck

• The per-mile fee for the moving truck

• How much Charlie paid for the truck

• The number of miles he drove

The graph represents the height of a burning candle.  What is the meaning of the y-intercept?

• the time it takes to burn the entire candle

• the rate at which the candle is losing height

• the change in the height of the candle each hour

• the original height of the candle