I believe the answer is D because the pathagreom theorum proves it true (excuse my terrible grammar)
First set everything to 0.
Giving you A= 1 , B= 1 and C= -5
Then input everything into the quadratic formula and either solve by hand or use a calculator.
Note exact values are found by hand, decimals are found using a calculator.
The answer is x-1 hope that helps not sure if it does