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3 years ago

Solve the equation x^2-4x-9=29

Mathematics

1 answer:

PtichkaEL [24]3 years ago

4 0

Answer:

x² - 4x - 9 = 29

x² - 4x - 9 - 29 = 0

x² - 4x - 38 = 0

Using the quadratic formula

$x = \frac{ - b± \sqrt{ {b}^{2} - 4ac } }{2a}$

Where

a = 1 , b = -4 c = - 38

So we have

$x = \frac{ - - 4± \sqrt{ { - 4}^{2} - 4(1)( - 38)} }{2(1)} \\ \\ x = \frac{4± \sqrt{16 +152 } }{2} \\ \\ x = \frac{4± \sqrt{168} }{ 2} \\ \\ x =2 ± \sqrt{42} \\ \\ \\ x = 2 + \sqrt{42} \: \: \: or \: \: \: x = 2 - \sqrt{42}$

Hope this helps you

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Gina started with the circle (x−2)2+y2=16. She translated it 4 units left and 1 unit down. Then she reduced the radius by 1 unit

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Answer:

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Step-by-step explanation:

Gina started with a circle with the given equation as,

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Since, standard equation of a circle is,

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Here (a, b) is the center of the circle and 'r' is the radius.

Therefore, from the given equation of the circle,

Center of the circle → (2, 0)

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She translated this circle 4 units left and 1 unit down.

Rule for the new center after translation will be,

(x, y) → (x - 4, y - 1)

(2, 0) → (2 - 4, 0 - 1)

→ (-2, -1)

Coordinates of the new center → (-2, -1)

Then she reduced the radius by 1 units.

Therefore, radius of the new circle = 4 - 1 = 3 units

Now we substitute these values in the standard equation of the circle to get the equation of the new circle.

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3 years ago

Jonathan wants to make mashed potatoes for eight people. He found a recipe which feeds two people and requires five ounces of po

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Answer:

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Step-by-step explanation:

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sergiy2304 [10]

Answer:

Step-by-step explanation:

We would apply the formula for determining compound interest which is expressed as

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Where

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Example 1:

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Example 2:

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