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McGraw Hill Integrated II, 2012

MH

McGraw Hill Integrated II, 2012 View details

6. The Law of Sines and Law of Cosines

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Exercise 69 Page 679

Notice that P is on the x-axis and that the triangle is a right isosceles triangle.

P(a,0) and Q(a,a)

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Notice that △ LPQ is a right isosceles triangle, where LP=PQ.

Since P is on the x-axis, its y-coordinate is 0. Additionally, because Q is on a vertical segment that passes through P, we know that P and Q have the same value for the x-coordinate. Therefore, the x-coordinate of P is equal to a.

Finally, since LP=PQ and LP=a, it must be that PQ=a. Therefore, the y-coordinate of Q is also a.

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Exercises p.674-679