Completing the square v003

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Completing the square

Completing the square of a quadratic equation.

P a r r o t e d i t i o n.

Let’s study together!

example 1.

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You were asked to complete the square of this quadratic equation:

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So we put the equation into our table.

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Highlight the part of the equation that contain x2 and x only.

Do not highlight the constant!

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Call this expression : p

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Rewrite 6x as (2)(3) x

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We need to do this to apply the formula :

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222 2 bababa

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Rewrite 6x as (2)(3) x.

We need to do this to apply the formula :

222 2 bababa

a = xb = 3

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222 2 bababa

Add 32 to p.

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Add 32 to p.

222 2 bababa a = xb = 3

Now we can apply the above formula.

Call this expression : q

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222 2 bababa

a = xb = 3

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222 2 bababa

a = xb = 3

There! We applied the formula.

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since

then

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since

then

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-9 + 5 is 4

Simplify y!

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Question :

Answer :

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Whew!! So tiring.Now I can sleep.