Answer:
9 weeks.
Explanation:
The equation 5w+16=61 models how many weeks, w it takes a puppy to reach a weight of 61 ounces after being born.
5w+16=61
Subtract 16 from both sides of the above equation.
5w+16-16=61-16
5w = 45
w = 9
Hence, the puppy will take 9 weeks to reach 61 ounces.