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How to transform this to vertex form 2x^2-18x+8

User Rockney
by
5.1k points

1 Answer

2 votes

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 form use the method of completing the square

• The coefficient of the x² term must be 1

y = 2(x² - 9x) + 8

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

y = 2(x² + 2 (-
(9)/(2)) x + (-
(9)/(2))² - (-
(9)/(2))²) + 8

y = 2(x -
(9)/(2))² - 2(
(81)/(4) + 8

= 2(x -
(9)/(2))² -
(65)/(2) ← in vertex form

User Stewart Lynch
by
5.3k points