Question

数学二次方程组,｛2x+3y=1 kx+(k-1)y=3的解中,x和y的值想等,k=

Answer 1

把 y = x 代入 2x + 3y = 1 得 :

2x + 3x = 1

x = 0.2

所以 y = 0.2

把 x = 0.2 ,y = 0.2 代入 kx + (k - 1)y = 3 得:

0.2k + 0.2(k - 1) = 3

0.2k + 0.2k - 0.2 = 3

0.4k = 3.2

k = 8