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Express in the form of ( (x + a)² + b ):

a) ( x² + 12x )
b) ( x² + 1/2x )

A. ( (x + 6)² + 36 )
B. ( (x + 6)² + 12 )
C. ( (x + 1/4)² + 47/16 )
D. ( (x + 1/4)² + 1/16 )

User Wallop
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1 Answer

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Final answer:

To express quadratic expressions in the form of ((x + a)² + b), we complete the square for each given expression. For (x² + 12x), the result is A. ((x + 6)² - 36), equivalent to option A. For (x² + 1/2x), the result is D. ((x + 1/4)² - 1/16), equivalent to option D.

Step-by-step explanation:

The question deals with expressing quadratic expressions in the form of ((x + a)² + b). To do this, we complete the square for each given quadratic expression.

For expression a) (x² + 12x):

Take half the coefficient of x, which is 6, and square it to get 36.

Add and subtract this square within the expression to get x² + 12x + 36 - 36.

Rewrite this as ((x + 6)² - 36), which can be expressed as ((x + 6)² + (-36)).

For expression b) (x² + 1/2x):

Take half the coefficient of x, which is 1/4, and square it to get 1/16.

Add and subtract this square within the expression to get x² + 1/2x + 1/16 - 1/16.

Rewrite this as ((x + 1/4)² - 1/16), which can be expressed as ((x + 1/4)² + (-1/16)).

Therefore, the correct expressions are:

A. ((x + 6)² - 36), which is equivalent to option A.

D. ((x + 1/4)² - 1/16), which is equivalent to option D.

User Quka
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