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《数学高分快速突破》陈向东
P253
120.Right triangle ABC is to be constucted in the xy-plane so that the right angle is at A and BC is parallel to the x-axis. The x- and y- coordinates of A, B, and C are to be integers that satisfy the inequalities -5<x<6 and 2<y<15. How many different triangles with these properties could be constucted?
A 120
B 1200
C 9000
D 11,880
E 12,000
答案是D,我在网上没找到类似的题目才来这里求助。其他类似的考题都是直角两边和XY轴平行,那种非常好求,但这个是直角边会和XY轴相交,还要求保证直角,我就不知道怎么做了,求大神帮助解答,谢谢。
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