A(x1, y1), B(x2, y2), C(x, y)AB的斜率为p = (y2 - y1)/(x2 - x1), 倾斜角a = arctan[(y2 - y1)/(x2 - x1)]按图,BC的倾斜角b=a + 85°,方程y - y2 = (x - x2)tanb
(1)从A作x轴的平行线,交AB于D,角A被分为上下两部分,下部分角BCD=180° - (85°+a) = 95° - a上部分角ACD = 85° - 角BCD = 85° - (95-a) = a - 10°, 此为AB的倾斜角AB的方程:y - y1 = (x - x1)tan(a - 10°)
(2)(1)(2)联立即得x, y...
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