Re: Which of the following must be true?
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09 Sep 2019, 22:47
Triangle P is an equilateral triangle, therefore, the area is (3)^(1/2) * a^(2) / 4. Which equals 25 * 3^(1/2). Approx 42.5
Triangle Q has an area of (1/2) * 10 * 10 = 50.
Also, we can determine the value of y from triangle Q. The triangle is an isosceles triangle, therefore the height must bisect the base. Using (5)^2 + (10)^2 = y^2, we get y = (125)^(1/2).
Triangle R has an area of 1/2 * y * y = 125/2 = 62.5
Therefore, P < Q < R => I < II < III.
Hence, the answer is B.