Question 702244
This system,
0.6x - 0.2y = -0.2
-0.03x - 0.07y = 0.17

will be a bit more comfortable if you multiply the entire first equation by 10, and the entire second equation by -100.


You will then have the equivalent system,
6x-2y=-2
3x+7y=-17


Solve either equation for x  OR  y; substitute the found expression into the other equation and solve for the other variable.  You now will have one of the values for that variable.


As example of a way to do the process, I pick the second equation and solve for y:
7y=-17-3x
y=(-17-3x)/7

Let me put this expression for y into the first equation.
6x-2(y)=-2
6x-2((-17-3x)/7)=-2
OR
{{{6*x-2*((-17-3*x)/7)=-2}}}


Now solve for x,.....continue until done....!


... a little bit further into the process,
clear the fraction by multiplying both sides by 7:
{{{42*x-2(-17-3*x)=-14}}}
{{{43*x+34+6*x=-14}}}
{{{48*x=-34-14}}}
{{{48*x=-48}}}, 
{{{x=-1}}}...... You can continue on from here...