Write an equation for the parabola whose vertex is at (4, 9) and which passes through (5, 24).

The general formula to form a parabole equation is written below.
y = a(x - h)² + k
with (x,y) is one of the points lies on the parabola, and (h,k) is the vertex of the parabola.

From the question above, we get this information
(x,y) = (5,24)
(h,k) = (4,9)
The remaining value to find is a. We need to find the value of a to form the equation. Input the numbers to the equation.
y = a(x - h)² + k
24 = a(5 - 4)² + 9
24 = a(1) + 9
24 = a + 9
24 - 9 = a
a = 15

Write the equation, without inputing the value of x and y
y = a(x - h)² + k
y = 15(x - 4)² + 9
This is the equation