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susann
Nov 7, 2006, 04:47 PM
how do you solve this problem for system of equations?

0.2x=0.5y=0.1
0.4x-0.2y=-1

Capuchin
Nov 8, 2006, 03:00 AM
Hi!

I'm assuming that the first = in the first equation should be a + or -, otherwise it is trivial.

You need to multiply one of the equations so that you can add or subtract them both to eliminate one of the variables, then you can get the value of the other variable, and use that value to infer the value of the other one.

So in your example, you could multiply all the numbers in the top equation by 2 (so you have 0.4x in both equations), then do the top equation minus the bottom one, solve the equation you get for y, then infer x by plugging your y value into one of the other equations.

Then you can use the equation you didn't plug into in order to check your answer.

Hope this helps