What is 20-200 is it postive or negative?

Which of the following equations is of the parabola whose vertex is at (4, 3), axis of symmetry parallel to the y-axis and focus at (4, -3)? a.) y+3=1/24 (x+4)^2 b.)y-3=-1/24 (x-4)^2 c.)x-4=-1/24 (y-3)^2

25 ! the line of best fit is h = 5a + 86. predict the height at age 16.

How is working backward similar to solving an equation?