Question 1192566
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Find the missing coordinate of P, using the fact that P lies on the unit circle in the given quadrant.


a) P( ,-15/17) Quadrant IV


b) P(2/5, ) Quadrant I
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<H3>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Part (a)</H3>

<pre>
The point is  P(x,-15/17), and it lies on the unit circle.  x is the unknown x-coordinate.


It means that  

    {{{x^2}}} + {{{(-15/17)^2}}} = {{{1^2}}},

    {{{x^2}}} + {{{225/289}}} = 1

    {{{x^2}}} = 1 - {{{225/289}}} = {{{(289-225)/225}}} = {{{64/225}}},

    x = {{{sqrt(64/225)}}} = +/- {{{8/15}}}.


Since the point is in Quadrant IV, x-coordinate is positive.


Therefore, the <U>ANSWER</U>  is x= {{{8/15}}}:  the missed coordinate is {{{8/15}}}.
</pre>

Solved.


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Solve part &nbsp;(b) &nbsp;in the same way.


You may report me about your progress.


If you do, &nbsp;please refer to the &nbsp;ID &nbsp;number of this problem, &nbsp;which is &nbsp;1192566.