document.write( "Question 104573: Multiply both sides of each equation by a common denominator to eliminate the fractions. then solve the system\r
\n" ); document.write( "\n" ); document.write( "x/2 + y/3 = 8\r
\n" ); document.write( "\n" ); document.write( "2x/3 + 3y/2 = 17
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Algebra.Com's Answer #76094 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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Solved by pluggable solver: Solving a linear system of equations by subsitution

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\n" ); document.write( " \"%281%2F2%29%2Ax%2B%281%2F3%29%2Ay=8\" Start with the first equation
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\n" ); document.write( " \"6%28%281%2F2%29%2Ax%2B%281%2F3%29%2Ay%29=%286%29%2A%288%29\" Multiply both sides by the LCD 6
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\n" ); document.write( " \"3%2Ax%2B2%2Ay=48\"Distribute and simplify
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\n" ); document.write( " \"%282%2F3%29%2Ax%2B%283%2F2%29%2Ay=17\" Start with the second equation
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\n" ); document.write( " \"6%28%282%2F3%29%2Ax%2B%283%2F2%29%2Ay%29=%286%29%2A%2817%29\" Multiply both sides by the LCD 6
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\n" ); document.write( " \"4%2Ax%2B9%2Ay=102\" Distribute and simplify
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\n" ); document.write( " Lets start with the given system of linear equations
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\n" ); document.write( " \"3%2Ax%2B2%2Ay=48\"
\n" ); document.write( " \"4%2Ax%2B9%2Ay=102\"
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\n" ); document.write( " Now in order to solve this system by using substitution, we need to solve (or isolate) one variable. I'm going to choose y.
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\n" ); document.write( " Solve for y for the first equation
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\n" ); document.write( " \"2%2Ay=48-3%2Ax\"Subtract \"3%2Ax\" from both sides
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\n" ); document.write( " \"y=%2848-3%2Ax%29%2F2\" Divide both sides by 2.
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\n" ); document.write( " Which breaks down and reduces to
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\n" ); document.write( " \"y=24-%283%2F2%29%2Ax\" Now we've fully isolated y
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\n" ); document.write( " Since y equals \"24-%283%2F2%29%2Ax\" we can substitute the expression \"24-%283%2F2%29%2Ax\" into y of the 2nd equation. This will eliminate y so we can solve for x.
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\n" ); document.write( " \"4%2Ax%2B9%2Ahighlight%28%2824-%283%2F2%29%2Ax%29%29=102\" Replace y with \"24-%283%2F2%29%2Ax\". Since this eliminates y, we can now solve for x.
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\n" ); document.write( " \"4%2Ax%2B9%2A%2824%29%2B9%28-3%2F2%29x=102\" Distribute 9 to \"24-%283%2F2%29%2Ax\"
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\n" ); document.write( " \"4%2Ax%2B216-%2827%2F2%29%2Ax=102\" Multiply
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\n" ); document.write( " \"4%2Ax%2B216-%2827%2F2%29%2Ax=102\" Reduce any fractions
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\n" ); document.write( " \"4%2Ax-%2827%2F2%29%2Ax=102-216\" Subtract \"216\" from both sides
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\n" ); document.write( " \"4%2Ax-%2827%2F2%29%2Ax=-114\" Combine the terms on the right side
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\n" ); document.write( " \"%288%2F2%29%2Ax-%2827%2F2%29x=-114\" Make 4 into a fraction with a denominator of 2
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\n" ); document.write( " \"%28-19%2F2%29%2Ax=-114\" Now combine the terms on the left side.
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\n" ); document.write( " \"cross%28%282%2F-19%29%28-19%2F2%29%29x=%28-114%2F1%29%282%2F-19%29\" Multiply both sides by \"2%2F-19\". This will cancel out \"-19%2F2\" and isolate x
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\n" ); document.write( " So when we multiply \"-114%2F1\" and \"2%2F-19\" (and simplify) we get
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\n" ); document.write( " \"x=12\" <---------------------------------One answer
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\n" ); document.write( " Now that we know that \"x=12\", lets substitute that in for x to solve for y
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\n" ); document.write( " \"4%2812%29%2B9%2Ay=102\" Plug in \"x=12\" into the 2nd equation
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\n" ); document.write( " \"48%2B9%2Ay=102\" Multiply
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\n" ); document.write( " \"9%2Ay=102-48\"Subtract \"48\" from both sides
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\n" ); document.write( " \"9%2Ay=54\" Combine the terms on the right side
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\n" ); document.write( " \"cross%28%281%2F9%29%289%29%29%2Ay=%2854%2F1%29%281%2F9%29\" Multiply both sides by \"1%2F9\". This will cancel out 9 on the left side.
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\n" ); document.write( " \"y=54%2F9\" Multiply the terms on the right side
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\n" ); document.write( " \"y=6\" Reduce
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\n" ); document.write( " So this is the other answer
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\n" ); document.write( " \"y=6\"<---------------------------------Other answer
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\n" ); document.write( " So our solution is
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\n" ); document.write( " \"x=12\" and \"y=6\"
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\n" ); document.write( " which can also look like
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\n" ); document.write( " (\"12\",\"6\")
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\n" ); document.write( " Notice if we graph the equations (if you need help with graphing, check out this solver)
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\n" ); document.write( " \"3%2Ax%2B2%2Ay=48\"
\n" ); document.write( " \"4%2Ax%2B9%2Ay=102\"
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\n" ); document.write( " we get
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\n" ); document.write( " graph of \"3%2Ax%2B2%2Ay=48\" (red) and \"4%2Ax%2B9%2Ay=102\" (green) (hint: you may have to solve for y to graph these) intersecting at the blue circle.
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\n" ); document.write( " and we can see that the two equations intersect at (\"12\",\"6\"). This verifies our answer.
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\n" ); document.write( " Check:
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\n" ); document.write( " Plug in (\"12\",\"6\") into the system of equations
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\n" ); document.write( " Let \"x=12\" and \"y=6\". Now plug those values into the equation \"3%2Ax%2B2%2Ay=48\"
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\n" ); document.write( " \"3%2A%2812%29%2B2%2A%286%29=48\" Plug in \"x=12\" and \"y=6\"
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\n" ); document.write( " \"36%2B12=48\" Multiply
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\n" ); document.write( " \"48=48\" Add
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\n" ); document.write( " \"48=48\" Reduce. Since this equation is true the solution works.
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\n" ); document.write( " So the solution (\"12\",\"6\") satisfies \"3%2Ax%2B2%2Ay=48\"
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\n" ); document.write( " Let \"x=12\" and \"y=6\". Now plug those values into the equation \"4%2Ax%2B9%2Ay=102\"
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\n" ); document.write( " \"4%2A%2812%29%2B9%2A%286%29=102\" Plug in \"x=12\" and \"y=6\"
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\n" ); document.write( " \"48%2B54=102\" Multiply
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\n" ); document.write( " \"102=102\" Add
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\n" ); document.write( "
\n" ); document.write( " \"102=102\" Reduce. Since this equation is true the solution works.
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\n" ); document.write( "
\n" ); document.write( " So the solution (\"12\",\"6\") satisfies \"4%2Ax%2B9%2Ay=102\"
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\n" ); document.write( " Since the solution (\"12\",\"6\") satisfies the system of equations
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\n" ); document.write( " \"3%2Ax%2B2%2Ay=48\"
\n" ); document.write( " \"4%2Ax%2B9%2Ay=102\"
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\n" ); document.write( " this verifies our answer.
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