Answer:
(2,-1)
Step-by-step explanation:
You just plug in the numbers. The order always starts as x then y. Basically that means in (2,1), the 2 would be the x and the 1 would be the y. In (4,-5), the 4 would be the x and the -5 would be the y and so forth.
Once you plug it in you get:
11(2)+4(-1)=18
3(2)+4(-1)=2.
When you plug the 2 and -1 in, they do equal 18 and 2 so you know that's the answer! :)