I just solved it and I'm pretty sure its only one solution, I took the bottom equation multiplied it by -3 then i canceled out the equations and got 9. So that would make it C.
Answer:
Step-by-step explanation:
Number of darts that hit the bull's eye = 15 x 40/100 = 6
Number of darts that did not hit the bull's eye = 15 - 6 = 9