(-4,10) is not a solution to the equation 10- 5x=y
Substitute/ Replace the x and y variable with their equivalent values. In this scenario x= -4 and y= 10. Now you have 10- 5(-4)=10.
Now solve as is, -5 times -4 is 20. 20+10=30, not 10.
So this is a INVALID statement.