An x value of 0 can only be plugged into the equation that has a domain that includes 0. The first function's domain is between -2 and -4, so 0 is not included in that domain. In the third function, the domain is between 1 and 3, so 0 is not included in that domain, either. The middle function's domain does include 0 (0 falls between -2 and 1) so we can only evaluate this function at an x value of 0.
The answer you are looking for is -11/10 or - 1 1/10.
To find this answer you must first make the denominators the same. To do this, multiply 2/5 by 2/2 to get 4/10. Finally, subtract the two fractions, keeping in mind the denominators stay the same. -7/10 - 4/10 = -11/10 or - 1 1/10.
