document.write( "Question 1042808: I Need help with solving an equation in two variables using elimination method. Here's the sum: 11x - 7y =xy , 9x - 4y = 6xy please.? \n" ); document.write( "

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I Need help with solving an equation in two variables using elimination method. Here's the sum: 11x - 7y =xy , 9x - 4y = 6xy please.?
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A system such as this is solved easiest by using the SUBSTITUTION method. However, let's use ELIMINATION, since that's the required method.\r
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document.write( "11x – 7y = xy ------- eq (i)
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document.write( "9x – 4y = 6xy ------- eq (ii)
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document.write( "- 44x + 28y = - 4xy ------- Multiplying eq (i) by - 4 ----- eq (iii)
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document.write( "  63x - 28y =  42xy ------- Multiplying eq (ii) by 7 ------ eq (iv)
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document.write( "19x = 38xy ------- Adding eqs (iii) & (iv)
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document.write( "11x - 7(½) = x(½) -------- Substituting ½ for y in eq (i)
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document.write( "22x - 7 = x -------- Multiplying by LCD, 2
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document.write( "22x - x = 7
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document.write( "21x = 7
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document.write( "x = , or \r
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document.write( "SUBSTITUTION would have resulted in a quadratic and a second solution set:  
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document.write( "Yes! It is that SIMPLE! \n" );
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