Question

write the equation for the vertical line that contains points E(10, -3)

Answer 1

Because a vertical line goes straight up and down, the only value of those two coordinates (10,-3) that matters is the x value. So your answer would be x=10.
There is no other way to write it other than that (I do believe) because a vertical line has an undefined slope. Therefore, the only equation that would fit here is x=10, because all values of the vertical line have 10 as the X value

Answer 2

Thanks already figured it out though