(3x-1)/2 - (x-y)/3=1 0.4x +0.3y=2.4 { { (x-y)/4 + (x+2y)/3=1
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(3x-1)/2 - (x-y)/3=1 0.4x +0.3y=2.4 { { (x-y)/4 + (x+2y)/3=1 (x-3)/3=(y+6)/5
求以上两个方程组的解,急.
(3x-1)/2 - (x-y)/3=1
{
0.4x +0.3y=2.4
(x-y)/4 + (x+2y)/3=1
{
(x-3)/3=(y+6)/5
求以上两个方程组的解,急.
(3x-1)/2 - (x-y)/3=1
{
0.4x +0.3y=2.4
(x-y)/4 + (x+2y)/3=1
{
(x-3)/3=(y+6)/5
![(3x-1)/2 - (x-y)/3=1 0.4x +0.3y=2.4 { { (x-y)/4 + (x+2y)/3=1](/uploads/image/z/19046907-27-7.jpg?t=%283x-1%29%2F2+-+%28x-y%29%2F3%3D1+0.4x+%2B0.3y%3D2.4+%7B+%7B+%28x-y%29%2F4+%2B+%28x%2B2y%29%2F3%3D1)
第一个方程组第一个式子两边同时乘以6得7x+2y=9(1),第二个式子同时乘以10得4x+3y=24(2).由(1)得y=4.5-3.5x,带入(2)得13x=-21,解得x=-21/13,再算y
同理解第二组
同理解第二组
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