Question

1. What is the vertex for the following quadratic function, y = 2x^2 - 4x + 5?

A). (1,3)
B). (3, 1)
C) (0,5)
D). (2,5)

Answer 1

A

Explanation:

Given a quadratic in standard form

y = ax² + bx + c ( a ≠ 0 )

Then the x- coordinate of the vertex is

x = -
`(b)/(2a)`

y = 2x² - 4x + 5 ← is in standard form

with a = 2 and b = - 4 , then

`x_(vertex)` = -
`(-4)/(4)` = 1

Substitute x = 1 into the equation for corresponding value of y

y = 2(1)² - 4(1) + 5 = 2 - 4 + 5 = 3

vertex = (1, 3 ) → A