Question

x+200y=20000 x+100y=15000 x=10000 y=50 怎么解来的(要详细）

Answer 1

x+200y=20000 ……①

x+100y=15000 ……②

则②式 - ①式,得

(X+200Y) - (X+100Y) = 20000 - 15000

即

100Y = 5000

解得Y = 5000/100 = 50

将Y的值代入 ②式得

X + 100×50 = 15000

即X + 5000 = 15000

解得X = 15000 - 5000 = 10000

综上

X = 10000

Y = 50