141k views
3 votes
How is y=2x^2-8x+9 rewritten in vertex form.

User Sled
by
7.9k points

1 Answer

6 votes

9514 1404 393

Answer:

y = 2(x -2)^2 +1

Explanation:

Start by factoring the leading coefficient from the x-terms.

y = 2(x^2 -4x) +9

Now identify the coefficient of x, -4, and figure half of that: -2. Square this number and add it inside the parentheses. At the same time, subtract the equivalent value outside parentheses. (The leading coefficient must be taken into account.)

y = 2(x^2 -4x +4) +9 -2(4)

Put in the desired form.

y = 2(x -2)^2 +1

This matches vertex form ...

y = a(x -h)^2 +k . . . . . . . . . vertical scale factor 'a'; vertex (h, k)

User TaylorAllred
by
8.1k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories