What value of n makes the equation 3(2-n)=3-n+1 true?

Plz me i need i will give a brain

Margaret is purchasing a house for $210,000 with a 15 year fixed rate mortgage at 4.75% interest she has made a 5% down payment the house is valued at 205,000 and the local tax rate is 3.5% homeowners insurance 600 per year what are her total monthly payment

y=2x−1 5x−4y=1 is (1,1)(1,1) a solution of the system?