document.write( "Question 133058: I am having problems with the following system of equations. The elimination method is supposed to be used, and the solution is to be in the form of integers or fractions.\r
\n" ); document.write( "\n" ); document.write( ".03x-0.2y=4
\n" ); document.write( ".04x+0.5y=63/19\r
\n" ); document.write( "\n" ); document.write( "Thanks!\r
\n" ); document.write( "\n" ); document.write( "Stephanie
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Algebra.Com's Answer #97283 by vleith(2983)\"\" \"About 
You can put this solution on YOUR website!
I assume you are being asked to eliminate rather than use substitution.\r
\n" ); document.write( "\n" ); document.write( "Given:
\n" ); document.write( "\".03x-0.2y=4\" Equation A
\n" ); document.write( "\".04x%2B0.5y=63%2F19\" Equation B\r
\n" ); document.write( "\n" ); document.write( "In order to use elimination, you want to get the coefficients of one of the variables (let's say y in this case) to be the same. Then you can simply add/substract one equation from the other to eliminate that variable. Once you have a single variable left, you can solve for it easily enough.\r
\n" ); document.write( "\n" ); document.write( "So let's manipulate equation A above. Let's multiply it by 5.
\n" ); document.write( "\"+0.15x+-+y+=+20\"\r
\n" ); document.write( "\n" ); document.write( "Now manipulate equation B. Let's multiply it by 2.
\n" ); document.write( "\"+0.8x+%2B+y+=+126%2F19\"\r
\n" ); document.write( "\n" ); document.write( "Then add these two equesitons to get:
\n" ); document.write( "\"+0.23x+=+20%2B+126%2F19+\"
\n" ); document.write( "solve for x, then use that to solve for y in any of the equations above.\r
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\n" ); document.write( "\n" ); document.write( "So now the question?? How did we know to use 5 and 2? Great question. We need to find a way to make the coefficients of one of the variables end up being equal in order to add/subtract them. You can look at Equation A and see that if you multiply by 5 it becomes 1. Then pick a number to multiply equation B to also se the y coefficient to 1 (in this case that number is 2).
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