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3 years ago

14

Solve by completing the square. w2 − 8w − 39 = 0 Write your answers as integers, proper or improper fractions in simplest form,

or decimals rounded to the nearest hundredth. w = [ ] or w = [ ]

1 answer:

adell [148]3 years ago

5 0

Answer:

4+√55= 11.42

4-√55= -3.42

Step-by-step explanation:

w² − 8w − 39 = 0
w²- 2*4w + 16- 55=0
(w-4)²=55
w-4=√55 ⇒ w= 4+√55= 11.42
w-4=- √55 ⇒ w= 4-√55= -3.42

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4 years ago

A circle is represented by the equation x2+y2=445. a) State the radius. b) Find y if point A(-9,y) is on this circle.

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Answer:

R= sqrt 445

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Step-by-step explanation:

Radius is the square root of 445

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3 years ago

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From the second equation, we can deduce

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Plug this in the first equation to get

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Refactor as

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And solve with the usual quadratic formula to get

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If we chose the positive solution, we have

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If we choose the negative solution, we have

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3 years ago

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kiruha [24]

Answer:

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Step-by-step explanation:

Given that,

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