154k views
3 votes
-x^2 +9x-12 in vertex form
please help !!!

1 Answer

1 vote

Answer:

see explanation

Explanation:

The equation of a parabola in vertex form is

y = a(x - h)² + k

where (h, k) are the coordinates of the vertex and a is a multiplier

To obtain this firm use the method of completing the square

Factor out - 1 from each term

y = - (x² - 9x + 12)
(33)/(4)

To complete the square

add/subtract (half the coefficient of the x- term )² to x² - 9x

y = - (x² + 2( -
(9)/(2))x +
(81)/(4) -
(81)/(4) + 12 )

= - ( (x -
(9)/(2))² -
(33)/(4) )

y = - (x -
(9)/(2) )² +
(33)/(4) ← in vertex form

User Rob Truxal
by
5.9k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.