document.write( "Question 537186: Hello, I am trying to figure out how to solve a system by the method of substitution. I have two problems in which I am having trouble with.\r
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document.write( "1) {x+3y=8
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document.write( " {y= 2x-9\r
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document.write( "and \r
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document.write( "2) {5x+2y=0
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document.write( " {x-3y=0\r
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document.write( "I'm confused on how to begin and the proper way to solve the problem, thank you for your help. \n" );
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Algebra.Com's Answer #352749 by KMST(5328)![]() ![]() You can put this solution on YOUR website! To solve a system of two linear equations by substitution, you solve for one of the variables in one equation and substitute the expression found in the other. \n" ); document.write( "Let's see how it works for your problems. \n" ); document.write( "1) \n" ); document.write( " \n" ); document.write( "Half of the work is already done for you because \n" ); document.write( " \n" ); document.write( "Multiply (apply distributive property) \n" ); document.write( " \n" ); document.write( "Collect like terms (distributive property backwards, adding apples to apples and x's to x's) \n" ); document.write( " \n" ); document.write( "Add 27 to both sides \n" ); document.write( " \n" ); document.write( "Divide both sides by 7 \n" ); document.write( " \n" ); document.write( "Then go back to find y \n" ); document.write( " \n" ); document.write( "So the answer is x=5 with y=1, usually expressed as the pair (5, 1). \n" ); document.write( "2) \n" ); document.write( " \n" ); document.write( "You need to solve for x or for y one of the two equations I would go with x in the second one: \n" ); document.write( " \n" ); document.write( "Then substitute in the first equation \n" ); document.write( " \n" ); document.write( "and then \n" ); document.write( "The solution is (0, 0). \n" ); document.write( " |