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4 years ago

Rewrite the equation by completing the squares x^2-x-20

Mathematics

1 answer:

yuradex [85]4 years ago

3 0

Answer: x = ¹/₂ ± √⁸¹

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Step-by-step explanation:

First write out the equation

x² - x - 20

Now we now write the equation by equating to 0

x² - x - 20 = 0

We now move 20 to the other side of the equation. So

x² - x = 20,

We now add to both side of the equation square of the half the coefficient of the (x) and not (x²) which is (1) . So, the equation now becomes

x² - x + ( ¹/₂ )² = 20 + ( ¹/₂ )²

x² - ( ¹/₂ )² = 20 + ¹/₄

( x - ¹/₂ )² = 20 + ¹/₄, we now resolve the right hand side expression into fraction

( x - ¹/₂ )² = ⁸¹/₄ when the LCM is made 4

Taking the square root of both side to remove the square,we now have

x - ¹/₂ = √⁸¹/₄

x - ¹/₂ = √⁸¹/₂

Therefore,

x = ¹/₂ ± √⁸¹

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3 years ago

Consider the system of components connected as in the accompanying picture. Components 1 and 2 are connected in parallel, so tha

bagirrra123 [75]

Answer:

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Step-by-step explanation:

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Let say subsystem 1 and subsystem 2

Subsystem 1 consist of 2 components, component 1 and component 2 that subsystem 1 works if and only if either component 1 or component 2 work

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Therefore P(subcomp1) = p(comp1) + p(comp2)

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3 years ago

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Hello there ^ _ ^ <br><br> I would like you to do me a favor and help me with this question. Thanks!

Marrrta [24]

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3 years ago

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4 years ago

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