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How to change from standard for to vertex form

User Native
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2 Answers

3 votes
standard form is
ax^2+bx+c=y
to change to vertex form
complete the square

HOW TO COMPLETE THE SQUARE
first, isolate the x terms
(ax^2+bx)+c=y
factor out a
a(x^2+(b/a)x)+c=y
take 1/2 of the coefient of the x term and square it
(b/a) time 1/2=b/(2a), square it,
(b^2)/(4a^2)
now add positive and negative inside parenthasees
a(x^2+(b/a)x+
(b^2)/(4a^2)-
(b^2)/(4a^2))+c=y
factor perfect square
a((
(x+ (b^2)/(4a^2))^2-a
(b^2)/(4a^2))+c=y
distribute

a(x+ (b^2)/(4a^2))^2 -a (b^2)/(4a^2)+c=y

a(x+ (b^2)/(4a^2))^2 - (b^2)/(4a)+c=y
that is vertex form and how to complete the square

for ax^2+bx+c=y
vertex form is

a(x+ (b^2)/(4a^2))^2 - (b^2)/(4a)+c=y
User MagerValp
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8.0k points
1 vote
If the equation is y = 3(x + 4)2 - 6, the value of h is -4, and k is -6. To convert a quadratic from y = ax2 + bx + c form to vertex form, y = a(x - h)2+ k, you use the process of completing the square. Let's see an example. Convert y = 2x2 - 4x + 5 into vertex form, and state the vertex.
User Khelili Miliana
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7.7k points