Question

What is the equation of the following graph in vertex form?

Parabolic function going down from the left through the (0,5) and turning at the (2,1) and continuing up towards infinity
A. y = (x − 2)2 + 1
B. y = (x − 1)2 + 2
C. y = (x + 2)2 + 1
D.y = (x + 2)2 − 1

Answer 1

f(x) = (x - 2)² + 1 answer A

Explanation:

∵ The form of the Parabolic function = (x - h)² + k , where (h , k) is the vertex of the curve (turning point)

∵ Turning point is (2 , 1)

∴ f(x) = (x - 2)² + 1

To check your formula substitute x and f(x) by 0 and 5 ⇒ the point which the curve passing through it

∵ (0 - 2)² + 1 = 4 + 1 = 5

∴ f(x) = (x - 2)² + 1