Question 238320
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Here's an example on how to solve equations by substitution.
{{{x+y=63}}}
{{{x-y=5}}}
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To solve by substitution:
1. Leave first equation alone for now.
2. Solve for y on the second equation.
3. Plug in this value (y) into the first eqn to find x
4. Once you know the x value, plug it again in the first equation to find y.
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{{{x-y=5}}}
{{{-y=5-x}}}
{{{y=-1(5-x)}}}
{{{y=-5+x}}}
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{{{x+y=63}}}
{{{x+(-5+x)=63}}}
{{{2x=63+5}}}
{{{2x=68}}}
{{{x=68/2}}}
{{{x=34}}}
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{{{x+y=63}}}
{{{34+y=63}}}
{{{y=63-34}}}
{{{y=29}}}
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Check:
{{{x+y=63}}} and {{{x-y=5}}}
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{{{34+29=63}}} and {{{34-29=5}}}