How many solutions does a system of linear equations in three variables have if in solving the system you correctly obtain the equation 12=12?

Me. i can't figure out this question. give an explanation too. .

Your friend uses c=50p to find the total cost, c, for the people, p, entering a local amusement park is the cost of admission proportional to the amount of people entering the amusement park? explain.

What multiplys to be 1 but adds up to be 4