Give the equation for a circle with the given center and radius. Center at (2, -9), radius = 3

Mathematics

1 answer:

olga2289 [7]3 years ago

8 0

Answer:

Step-by-step explanation:

The standard form of the equation of a circle is

(x - h)² + (y - k)² = r²

where (h, k) are the coordinates of the centre and r is the radius

Here (h, k) = (2, - 9) and r = 3, thus

(x - 2)² + (y - (- 9))² = 3², that is

(x - 2)² + (y + 9)² = 9 → B

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Find the exact value of tan( cos^-1 ( -5/13))

trasher [3.6K]

Answer:

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Step-by-step explanation:

Let cos a = -⁵/₁₃

Then tan a = sin a/cos a

= [√(1 - cos²a)]/cos a

= {√[1 - (-⁵/₁₃)²]}/(-⁵/₁₃)

= -[√(1 - ²⁵/₁₆₉)] × ¹³/₅

= -[(√(¹⁴⁴/₁₆₉ )] × ¹³/₅

= -¹²/₁₃ × ¹³/₅

= -¹²/₅

tan(arccos (-⁵/₁₃)) = -¹²/₅

The diagram shows the 2nd quadrant of a circle with radius 13, cos a = -⁵/₁₃, and tan a = ¹²/₍₋₅₎ = -¹²/₅.

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3 years ago

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Kitty [74]

Answer:

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