Answer:
x = 5
Explanation:
Discontinuities arise in function definitions from several sources. One of them is the boundary of the piecewise definition. Here, the boundary is at x=5.
The function is defined to be f(5) = 0, but the limit from above as x approaches 5 is 5²-10 = 15. This value is not equal to zero (the value of f(5)), so there is a discontinuity at that point.