What are the solutions to the equation(5x-15)^{2}= -100? Show your work.
a.) x=3+2i sqrt root 5 and x=3- 2i sqrt root 5
b.) x=3+2i and x=3- 2i
c.) x- (-i) sqrt root 5 and x= i sqrt root 5
d.) x=1 and x=5