y=2/3x -1 does (9, -10) satisfy the function
The function is: y = (2/3)x - 1
Let us find the value of the function, y, when x = 9.
y(x=9) = (2/3)*9 - 1
y = (18/3) - 1
y = 6 - 1
y = 5
i.e. y does not requal -10.
Therefore, the point (9, -10) does not satisfy the equation: y = (2/3)x - 1