Question 516236
0.3x-0.2y=4...............(1)
0.2x + 0.3y=29/19.........(2)

Make above equations more simple

3x/10+2y/10=4
Multiply by 10 both sides of above equation
3x+2y=40.................(3)
2x/10+3y/10=29/19
Multiply by 10 both sides of above equation
2x+3y=290/19.............(4)

Multiply (3) by -2 and (4) by 3 and add the resultant equations
-6x-4y=-80
6x+9y=870/19
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5y=870/19-80
5y=(870-1520)/19
5y=-650/19
5y/5=-650/19/5
y=-130/19
Put the value of y in (3)
3x+2y=40.................(3)
3x+2(-130/19)=40
3x-260/19=40
Multiply by 19 both sides
57x-260=760
57x=760+260
57x=1020
57x/57=1020/57
x=1020/57

x, y =1020/57,-130/19

Check
Put the values of x and y in (4)
2x+3y=290/19.............(4)
2(1020/57)+3(-130/19)=290/19
2040/57-390/19=290/19
(2040-1170)/57=290/19
870/57=290/19
290/19=290/19