(1)
二者均大于或等于零,而和为零,二者均为零:
a + b = 34
- a + b = -18
b = 8, a = 26
A(26, 0), B(0, 8)
(2)
C(24, 8)
t秒时,BP = t, QA = 2t, OQ = 26 - 2t
BP = OQ, t = 26 - 2t, t = 36/3
(3)
四边形BPQO的面积S = (1/2)(BP + OQ)*OB
= (1/2)(t + 26 - 2t)*8 = 4(26 - t)
四边形PQAC的面积S' = (1/2)(PC + QA)*OB
= (1/2)(24 - t + 2t)*8
= 4(24 + t)
4(26 - t) < 4(24 + t)
t > 1
答案: 1 < t < 13
a+b=34
b-a=18
a=8
b=26
感觉第二问题目是错的