If x and kare integers and (12^x)[4^(2x+1)] = (2^k)(3^2),what is the value of k?
A. 5
B. 7
C. 10
D. 12
E. 14
参考答案：E
题目翻译：有等式(12^x)[4^(2x+1)] = (2^k)(3^2)，其中k和x都是整数，求k。
题目全解：等式右边=[4^(k/2)]*(3^2)=[4^(k/2-2)](12^2);
因此，x=2，2x+1=k/2-2;
k=14.
If(y+3)(y-1) – (y-2)(y-1) = r(y-1), what is the value of y?
(1) r^2 = 25
(2) r = 5
A.Statement (1) ALONE is sufficient, but statement (2) alone is notsufficient.
B.Statement (2) ALONE is sufficient, but statement (1) alone is notsufficient.
C. BOTH statementsTOGETHER are sufficient, but NEITHER statement ALONE issufficient.
D. EACHstatement ALONE is sufficient.
E.Statements (1) and (2) TOGETHER are NOT sufficient.
参考答案：E
题目翻译：有等式 (y+3)(y-1) – (y-2)(y-1) = r(y-1), 求y值。
题目全解：左边等于y^2+2y-3-y^2+3y-2=5y-5=5(y-1)
如果5(y-1)=r(y-1),即(5-r)(y-1)=0;
如果r=5,y值不可求;r!=5,y值为1。所以选E。注意，条件(1)，r等5或者-5，y值不确定。
What isthe sum of the integers from -190 to 195, inclusive?
A. 0
B. 5
C. 375
D. 875
E. 965
参考答案：E
题目翻译：负190到正195，整数的和是多少呀?
题目全解：-190到190都抵消了，答案是191+192+193+194+195=965.
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