To determine if the given point lies on both given lines, replace the values of x and y of the point into each equation and verify the equation, as follow:
point: (-2,-2)
x = -2
y = -2
first equation:
2x + 3y - 10 = 2(-2) + 3(-2) + 10 = -4 - 6 + 10 = -10 + 10 = 0
second equation:
3x = 3y
3(-2) = 3(-2)
-6 = -6
As you can notice, when you replace x and y by the values of the point the equation is consistent.
Then, you can conclude that the point lies on both lines.