11. In ΔPQR, if PQ = x + 2, and PR = y, which of the three angles
of ΔPRQ has the greatest degree measure? (1) y = x + 3 (2) x = 2 Explanation: In any triangle, the largest angle is opposite the longest side. To
determine the longest sidesuffices to determine whether y > x + 2.
Since x + 3 > x + 2, it follows from (1) that y > x + 2. Statement (1) alone is therefore sufficient. From (2) it follows
that PQ = 2 and QR = 4. Thus, y can be any value between 2 and 6; it follows that y > x, but it cannot
be concluded that y > x + 2. Statement (2) alone is therefore not sufficient. Therefore,
statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer the question.
百思不得其解 ,og好像少写了 OR为X 这个条件。 |