Jimmy L. answered  07/02/19
Ivy League Freshman and 99th Percentile SAT Scorer
The function is continuous for C = 5/3.
For the piecewise function to be continuous, the left and right sides have to meet. That is to say, the top equation at x = 5 has to equal the bottom equation at x = 5.
So,
(5)^2 - C = 4(5) + 2C
25 - C = 20 + 2C
5 = 3C
C = 5/3
Hope that helped, Mycah!