Question

Joe tracked the height of his Dalmatian puppy from age 13 weeks to 25 weeks. He graphed the data and determined the line of best fit is y = 1.12x + 28.78 where x is the age in weeks and y is the height in centimeters. How old was the puppy when he was 54 centimeters tall? Round to the nearest tenth.
a. 22.5 weeks
b. 28.2
c. 73.9
d. 89.3

Answer 1

Answer:

22.5 weeks

Step-by-step explanation:

y = 1.12x + 28.78 represents the height of the puppy.  Here that height is 54 cm:

Then 54 = y = 1.12x + 28.78

Combining the constants, we get 1.12x = 25.22.  Dividing both sides by 1.12, x turns out to be 22.5 weeks.