How do you find y if the point (5,y) is on the terminal side of theta and $cos θ = \frac{5}{13}$ $costheta=5/13$ ?

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How do you find y if the point (5,y) is on the terminal side of theta and $cos θ = \frac{5}{13}$ $costheta=5/13$ ?

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Answer 1 · 2017-12-02T04:13:00

$y = \pm 12$ $y = +- 12$

Explanation:

$cos t = \frac{5}{13}$ $cos t = 5/13$
$sin t = \frac{y}{13}$ $sin t = y/13$
Use trig identity:
${sin}^{2} t + {cos}^{2} t = 1$ $sin^2 t + cos^2 t = 1$
$\frac{y^{2}}{169} + \frac{25}{169} = 1$ $y^2/169 + 25/169 = 1$
$y^{2} + 25 = 169$ $y^2 + 25 = 169$
$y^{2} = 169 - 25 = 144$ $y^2 = 169 - 25 = 144$
$y = \pm 12$ $y = +- 12$
There are 2 arcs (or angles) t that have the same cos value (5/13).

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How do you find y if the point (5,y) is on the terminal side of theta and $cos θ = \frac{5}{13}$ $costheta=5/13$ ?

1 Answer

Explanation:

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Humanities

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How do you find y if the point (5,y) is on the terminal side of theta and cosθ=513costheta=5/13?

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Explanation:

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How do you find y if the point (5,y) is on the terminal side of theta and $cos θ = \frac{5}{13}$ $costheta=5/13$ ?