document.write( "Question 280013: How do I solve the system using the substitution method and show work?
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document.write( "2x+3y=2
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document.write( "x+3y=10 \n" );
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Algebra.Com's Answer #203503 by jsmallt9(3758)![]() ![]() ![]() You can put this solution on YOUR website! (A solution provided by another tutor did not use the Substitution Method.) \n" ); document.write( "Substitution Method
\n" ); document.write( "Let's see how this works on your system of equations: \n" ); document.write( "2x + 3y = 2 \n" ); document.write( "x + 3y = 10 \n" ); document.write( "1. Solve one equation for one of the variables. Look for a variable with a coefficient of 1 (or -1), if any. If there is such a variable, this will be a good choice. So I am going to solve the second equation for x. All I have to do is add -3y to (or subtract 3y from) each side. This gives me: \n" ); document.write( "x = -3y + 10 \n" ); document.write( "2. Substitute for this variable in the other equation. We used the second equation for step 1 so we will substitute for x in the first equation, using the expression we got in step 1: \n" ); document.write( "2(-3y + 10) + 3y = 2 \n" ); document.write( "(Notice the use of parentheses. This is important when making substitutions. In this case it helps us know that the Distributive Property will be needed.) We now have an equation with one variable, y. \n" ); document.write( "3. Solve this one variable equation. \n" ); document.write( "Simplify: \n" ); document.write( "-6y + 20 + 3y = 2 \n" ); document.write( "-3y + 20 = 2 \n" ); document.write( "Isolate the variable term (by subtracting 20 from each side): \n" ); document.write( "-3y = -18 \n" ); document.write( "Divide by -3: \n" ); document.write( "y = 6 \n" ); document.write( "4. Use this result to find the other variable by substituting into one of the original equations: \n" ); document.write( "2x + 3(6) = 2 \n" ); document.write( "2x + 18 = 2 \n" ); document.write( "2x = -16 \n" ); document.write( "x = -8 \n" ); document.write( "So the solution for this system is (-8, 6). \n" ); document.write( " |