If f(x) is a continuous function defined for all real numbers, f(-1)=1, f(-5)=-10, and f(x)=0 for one and only one value of x, then which of the following could be that x value?

a) -6
b) -5
c) -4
d) 0

1 answer

It has to be between -1 and -5. Are any of the answers in that range?