Question

Help me in math please

Answer 1

Answer: Choice A

Proof:
Replace x with 1 and y with 2. This is because (x,y) = (1,2) so x = 1 and y = 2.

Doing both replacements and simplifying leads to...

2*x - y = 0
2*1 - 2 = 0
2 - 2 = 0
0 = 0

That confirms (x,y) = (1,2) is a point on the line.
It confirms (1,2) is a solution to the equation.