Question

Does the point (4,2) satisfy the equation y = x

Answer 1

No,

y=x means the y part of the co-ordinate must be the same as the x part of the co-ordinate

So (4,4) and (2,2) would work but NOT (4,2)

Answer 2

No, because if you plug in 2 into the equation y=x, y will be equal to 2, instead of 4.