Question 173838
1.{{{y=5x}}}
2.{{{2x+y=28}}}
Directly substitute eq. 1 into eq. 2,
 2.{{{2x+y=28}}}
{{{2x+(5x)=28}}}
{{{7x=28}}}
{{{x=4}}}
From eq. 1,
1.{{{y=5x}}}
{{{y=5(4)}}}
{{{y=20}}}
The solution is x=4, y=20. 
To check the solution, plug the solution into the equations.
1.{{{y=5x}}}
{{{20=4(5)}}}
{{{20=20}}}
True.
 2.{{{2x+y=28}}}
 {{{2(4)+20=28}}}
{{{8+20=28}}}
{{{28=28}}}
True.
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.
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The solutions led to true statements.
They are good solutions.
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.
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x=4
y=20