The formula for an average of three numbers is (x+y+z)/3. So if V equals the average, then we find the formula
V = (x+y+z)/3
We are now looking for x. We can divide each of the variables in the parentheses by 3, making the formula
V = x/3 + y/3 + z/3
So now bring the unwanted variables to the same side as V.
V - y/3 - z/3 = x/3
Now multiply both sides by 3 to find x.
3V - y - z = x
x = 3V - y - z
1) 4c*2
2)a*2
3)c
.........................*=square
Answer: i think it is... x = -19