Question

已知C是线段上的一点,且AC大于BC,AC的平方等于AB乘以BC若AB等于10厘米,求线段BC的长.(精确到百分位)

Answer 1

设 bc = x

(10-x)2 = 10 * x

100 - 20x + x2 = 10x

x2 - 30x + 100 = 0

x = 15 - 11.18 = 3.82

验证

3.82 * 10 = (10-3.82)2 = 38.2

bc = 3.82 cm