Question

Is (2, 1) a solution to y = 2x?

Answer 1

no

Answer 2

no
plug x=2 and y = 1
into the equation
gives y = 1 and 2x = 4

Answer 3

(1,2) is a solution

Answer 4

if u substitute values of x and y, u get

1 = 2*2 which is not true...