The answer is yes since if we were to check what y coordinate does the point with x value of 3 have, we would get that...
y = x + (-6)
y = 3 + (-6)
y = - 3
Therefore the point with x value of 3 will have a y coordinatie with a value of -3, and this is how we know that point (3, -3) satisfies equation y = x + (-6).
