What’s the answer or is a write ur self answer so I can help !
Create a a system of 2 equations: 2x + y = 27 and 2y + x = 9, with x being the first number and y being the second. solve for the two variables and you'll get the first number is 15 and the second is -3.
4^2+3^2=25
sqrt 25= 5
Answer is 5
Any with an odd number of minus signs.
Perhaps the 1st and 4th, if I read it right.