Question

A scatter plot at the right was created to show the length of a person's vacation and the weigh the suitcase they packed. use your equation to predict the weight of a suitcase for someone taking a 12 day trip.

Answer 1

The equation of the line and the weight of suitcase for a 12-days trip would be : y = 5x + 15 and 75 lbs respectively.

The equation of the line expressed in slope-intercept form is expressed thus ;

• y = bx + c ; b = slope and c = intercept

Using the pair of points to determine the slope and equation of the line :

• (6, 45) ; (1, 20)

The slope = change in y / change in x

slope = (20 - 45) / (1 - 6) = -25/-5 = 5

Now we ;

y = 5x + c

We can then calculate c ;

45 = 5(6) + c

45 = 30 + c

c = 15

The equation of the line is : y = 5x + 15

B.)

For a 12-day trip

• x = 12

y = 5(12) + 15

y = 60 + 15

y = 75

Hence, the weight of suitcase would be 75