单选题
【正确答案】
C
【答案解析】Each column is the product of 11 integers, one of which is 0. Since 0 times any number is 0, each column is 0. The columns are equal (C).
【正确答案】
C
【答案解析】Since by KEY FACT J2 the measure of an exterior angle of a tri-angle is equal to the sum of the measures of the two opposite interior angles, 140 = 70 + y, and so y = 70. Therefore, angles A and B are equal, and by KEY FACT J3 so are the sides opposite them: AC = BC. The columns are equal (C).
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**If you don't know the theorem about the exterior angle, first find x: x + 140 = 180 x = 40. Then, since the sum of the measures of the three angles of a triangle is 180, y = 70.
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**If you don't know the theorem about the exterior angle, first find x: x + 140 = 180 x = 40. Then, since the sum of the measures of the three angles of a triangle is 180, y = 70.
【正确答案】
C
【答案解析】If a ≠ b and ax=bx, then x must be 0.
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【正确答案】
B
【答案解析】Every factor of n is a factor of 2n, but 2!is a prime factor of 2n, which is not a factor of n (since n is odd). So, 2n has more prime factors than n. Column B is greater.