Question

Which is not an equation of the line that passes through the points (1, 1) and (5, 5)?

Answer 1

$(1,\ 1)\to x_1=1,\ y_1=1\to x_1=y_1\\\\(5,\ 5)\to x_2=5,\ y_2=5\to x_2=y_2\\\\\text{Therefore we have the equation}\ y=x\\\\\text{subtract y from both sides}\\\\\boxed{x-y=0\to\boxed{B}}\to\boxed{y-x=0\to\boxed{A.}}\\\\Answer:\ C.\ -x-y=0$