Lia has a dog and a cat the pets weigh 16 pounds The dog weighs 3 times as much as the cat

The weight of the dog is 12 pounds and the weight of the cat is 4 pounds.

Step-by-step explanation:

Let d represent the weight of the dog. Let c represent the weight of the cat.

Let's make a system of equations.

d+c=16

d=3c

We can use subsitution.

3c+c=16

4c=16

c=4

We can subsitute back into one of the two equations to find the weight of the dog.

d=3c

d=3 (4)

d=12

The weight of the dog is 12 pounds and the weight of the cat is 4 pounds.