Question

Write an equation of the parabola in vertex form

Answer 1

y = -1/9(x - 3) + 1.

Explanation:

THe vertex is at (3, 1) so we can write:

y = a(x - 3)^2 + 1 where a is a constant.

Now the point 1, 5/9) is on the parabola so:

5/9 = a(1 - 3)^2 + 1

5/9 = 4a + 1

4a = 5/9 - 1 = -4/9 so

a = -4/9 / 4

a = -1/9

So the equation is y = -1/9(x - 3) + 1.