26=8+v i dont know how to do this and i need

26 = 8 + v equals v = 18.

First, subtract 8 from both sides. Your problem should look like 26 - 8 = v.
Second, simplify 26 - 8 to get 18. Your problem should look like 18 = v.
Third, switch sides. Your problem should look like v = 18, which is the correct answer.

Do you need with the x value for the minimum? its always between the two intercepts for a parabola