Jen knows that (-1, 41) and (5, 41) lie on a parabola defined by the equation y = 4x² - 16x + 21. What are the coordinates of the vertex?

Wribreeminsl

Wribreeminsl

Answered question

2020-10-25

Jen knows that (-1, 41) and (5, 41) lie on a parabola defined by the equation y = 4x² - 16x + 21. What are the coordinates of the vertex?

Answer & Explanation

unessodopunsep

unessodopunsep

Skilled2020-10-26Added 105 answers

The vertex of a parabola lies on the axis of symmetry which divides the parabola into two mirror images. Notice that the two points are reflection of each other about a vertical line since they have the same yy-coordinate. This means that the average of their xx-coordinates is the xx-coordinate of the vertex:
x=1+52=2
To find the y-coordinate of the vertex, substitute x=2 to the equation:
y=4(2)216(2)+21=5
So, the vertex is at:
(2,5)

Do you have a similar question?

Recalculate according to your conditions!

Ask your question.
Get an expert answer.

Let our experts help you. Answer in as fast as 15 minutes.

Didn't find what you were looking for?