Multiply 4x-y=5 by 3 (everything so it would be 12x -3y =15. multiply 3x +y = 16 by 4 (12x- 4y = 64) set it up like an elimination problem 12x -3y =15 -12x-4y =64 ---------------- 1x = -49 x= -49
plug x back into the original equation-----> 4(-49) -y =5 -169 -y = 5 +169. +169 x = 174
A pair of tires is $216, so at that rate 4 tires would be $432. The managers special is $380 so $432-$380=$52 savings for 4. $52\4=$13 savings per tire.