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lana66690 [7]
4 years ago
8

Solve x2 - 8x = 20 by completing the square. Which is the solution set of the equation?

Mathematics
1 answer:
Artyom0805 [142]4 years ago
3 0

Answer:

{-2,10}

Step-by-step explanation:

x^2 - 8x = 20

Take the coefficient of x

-8

Divide by 2

-8/2 =-4

Square it

(-4)^2 =16

Add this to each side

x^2 - 8x+16 = 20+16

x^2 - 8x+16 = 36

The left hand side becomes( x + (-8/2) )^2

(x - 4)^2 = 36

Take the square root of each side

sqrt((x - 4)^2) =±sqrt( 36)

x-4 = ±6

Add 4 to each side

x-4+4 = 4±6

x = 4±6

x = 4+6       x = 4-6

x = 10        x = -2

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Answer:

The customer can conclude that the company's claim is correct

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