Explanation:
oh ? now that is really very simple. you take the value of x, put it into the equation, calculate the resulting y value, and put that y value into your table.
y = -3x + 8
x = -1
y = -3×-1 +8 = 3 + 8 = 11
x = 0
y = -3×0 + 8 = 8
x = 1
y = -3×1 + 8 = -3 + 8 = 5
x = 2
y = -3×2 + 8 = -6 + 8 = 2
you see how easy, simple and straight forward that is ? that is in fact how functions work.