document.write( "Question 516236: How do I solve 0.3x-0.2y=4 and 0.2x + 0.3y=29/19 using the elimination method? \n" ); document.write( "
Algebra.Com's Answer #344297 by Maths68(1474) You can put this solution on YOUR website! 0.3x-0.2y=4...............(1) \n" ); document.write( "0.2x + 0.3y=29/19.........(2)\r \n" ); document.write( "\n" ); document.write( "Make above equations more simple\r \n" ); document.write( "\n" ); document.write( "3x/10+2y/10=4 \n" ); document.write( "Multiply by 10 both sides of above equation \n" ); document.write( "3x+2y=40.................(3) \n" ); document.write( "2x/10+3y/10=29/19 \n" ); document.write( "Multiply by 10 both sides of above equation \n" ); document.write( "2x+3y=290/19.............(4)\r \n" ); document.write( "\n" ); document.write( "Multiply (3) by -2 and (4) by 3 and add the resultant equations \n" ); document.write( "-6x-4y=-80 \n" ); document.write( "6x+9y=870/19 \n" ); document.write( "------------------ \n" ); document.write( "5y=870/19-80 \n" ); document.write( "5y=(870-1520)/19 \n" ); document.write( "5y=-650/19 \n" ); document.write( "5y/5=-650/19/5 \n" ); document.write( "y=-130/19 \n" ); document.write( "Put the value of y in (3) \n" ); document.write( "3x+2y=40.................(3) \n" ); document.write( "3x+2(-130/19)=40 \n" ); document.write( "3x-260/19=40 \n" ); document.write( "Multiply by 19 both sides \n" ); document.write( "57x-260=760 \n" ); document.write( "57x=760+260 \n" ); document.write( "57x=1020 \n" ); document.write( "57x/57=1020/57 \n" ); document.write( "x=1020/57\r \n" ); document.write( "\n" ); document.write( "x, y =1020/57,-130/19\r \n" ); document.write( "\n" ); document.write( "Check \n" ); document.write( "Put the values of x and y in (4) \n" ); document.write( "2x+3y=290/19.............(4) \n" ); document.write( "2(1020/57)+3(-130/19)=290/19 \n" ); document.write( "2040/57-390/19=290/19 \n" ); document.write( "(2040-1170)/57=290/19 \n" ); document.write( "870/57=290/19 \n" ); document.write( "290/19=290/19\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |