用解二的思路，也可以由高来列方程。
wxcfan123
2024-01-10 12:48:56
( reads)
从点到三边距离和是常数，得方程 b - x + 5x/7 + 8x/7 = x + b - 5x/7 + b - 8x/7 .
b - x = 10x/7 + 16x/7 - 3x = 5x/7. 阴影面积 = 7 * 5/7 = 5.
从点到三边距离和是常数，得方程 b - x + 5x/7 + 8x/7 = x + b - 5x/7 + b - 8x/7 .
b - x = 10x/7 + 16x/7 - 3x = 5x/7. 阴影面积 = 7 * 5/7 = 5.