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Find the missing coordinate of P , using the fact that P lies on the unit circle in the given quadrant. coordinates QUADRANT P(2/3, ______) II

User Andrija
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2 Answers

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Final answer:

To find the missing coordinate of point P in quadrant II on the unit circle, use the given x-coordinate and determine the appropriate sign for the missing y-coordinate.

Step-by-step explanation:

To find the missing coordinate of point P, we need to use the fact that P lies on the unit circle in the given quadrant. In quadrant II, the x-coordinate is negative and the y-coordinate is positive. Since the x-coordinate is given as 2/3, the y-coordinate should be positive. Therefore, the missing coordinate of P is (2/3, y), where y is positive.

User Marissajmc
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Final Answer:

The missing y-coordinate of point P in the second quadrant, lying on the unit circle with x-coordinate
\( (2)/(3) \), is \( (√(5))/(3) \). Therefore, the coordinates of P are
\( \left((2)/(3), (√(5))/(3)\right) \).

Step-by-step explanation:

In the second quadrant of the Cartesian coordinate system, the x-coordinate is negative, and the y-coordinate is positive. Since P lies on the unit circle, the distance from the origin to P is 1.

Given that the x-coordinate of P is
\( (2)/(3) \), we can use the Pythagorean theorem to find the y-coordinate. The Pythagorean theorem states that for any right-angled triangle, the square of the length of the hypotenuse
(\(c\)) is equal to the sum of the squares of the lengths of the other two sides
(\(a\) and \(b\)).

In this case, let (a) be the x-coordinate
(\( (2)/(3) \)), (b) be the y-coordinate, and (c) be the distance from the origin to P (which is 1 on the unit circle).

The Pythagorean theorem equation is:


\[ a^2 + b^2 = c^2 \]

Substitute the given values:


\[ \left((2)/(3)\right)^2 + b^2 = 1^2 \]


\[ (4)/(9) + b^2 = 1 \]

Now, solve for \(b\):


\[ b^2 = 1 - (4)/(9) \]


\[ b^2 = (5)/(9) \]


\[ b = \pm \sqrt{(5)/(9)} \]

Since P is in the second quadrant where the y-coordinate is positive, the y-coordinate of P is
\( (√(5))/(3) \).

Therefore, the coordinates of P in the second quadrant are
\( \left((2)/(3), (√(5))/(3)\right) \).

User Kieren Johnstone
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