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4 years ago

What number would you add to the equation below to complete the square?x2 + 4x = 0?

1 answer:

7 0

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Equation
------------------------------------------------------------------
x² + 4x = 0

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Add a constant
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x² + 4x + (4/2)² - (4/2)² = 0 ← Add 2² to form perfect square

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Evaluate bracket
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x² + 4x + 2² - 2² = 0

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Form the perfect square
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(x + 2)² = 4

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Square root both sides
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(x+2) = $\pm$ √4

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Evaluate the square root
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(x+2) = $\pm$ 2

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Solve x
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x = 2 - 2 or x = -2 - 2

x = 0 or -4

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Answer: The constant to add is 4 and the value of x = 0 or -4
------------------------------------------------------------------

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Answer:

Total distance Alicia run in kilometer = 8 Kilometer

Step-by-step explanation:

Given:

Total distance Alicia run = 5 miles

1 mile ≈ 1.6 kilometer

Find:

Total distance Alicia run in kilometer

Computation:

Total distance Alicia run in kilometer = 1.6 × 5

Total distance Alicia run in kilometer = 8 Kilometer

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3 years ago

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The three coins could land any these 8 ways:

HHH, HHT, HTH, HTT, THH, THT, TTH, TTT

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P(1 head) = 3 ways out of 8 or 3/8

P(0 heads) = 1 way out of 8 or 1/8

x=Winnings P(x) E(x)=x�P(x)

$3 1/8 $.375

$2 3/8 $.75

$1 3/8 $.375

-$10 1/8 -$1.25

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Total expectation = $ .25

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3 years ago

Christina buys 3 DVDs . 2 of the DVDs cost X+Y . Write an expression that shows the amount the 3 DVDs cost

-BARSIC- [3]

Answer:

3/2(x+y)

Step-by-step explanation:

The cost of 2 DVD is x+y

Divide by 2 to get the cost of one DVD

(x+y) /2

Multiply by 3 to get the cost of 3

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3 years ago

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3 years ago

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Natalija [7]

Length of the walkway that needs to be tiled = 60 feet
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4 years ago

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