3x
We need to substitute x with 5 because the question is asking how many squats Carlos has completed if he completed 5.
3 x 5 = 15
Therefore, Carlos completed 15 squats as part of his football workout.
By the way, this question is very simple and basic. I recommend reviewing Algebra for your benefit/
300 may be the answer if not you need to use matheay
P=k•l•v
This is an example of joint variation that takes the form: z=kxy, where k=constant of proportionality.