Question 809300
Is this the problem:
{{{ y - 3 = (2/5 )*( x + 1 ) }}} ?
If so, 
first add {{{ 3 }}} to both sides
{{{ y = (2/5 )*( x + 1 ) + 3 }}} 
Then multiply both sides by {{{ 5 }}}
{{{ 5y = -2*( x + 1 ) + 15 }}}
Now do the multiplication on the right side
{{{ 5y = 2x + 2 + 15 }}}
{{{ 5y = 2x + 17 }}}
Now subtract {{{ 17 }}} from both sides
{{{ 5y - 17 = 2x }}}
Now divide both sides by {{{ 2 }}}
{{{ x = (1/2)*( 5y - 17 ) }}}
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There is a simple way to check answer
Just pick any number for {{{x}}} 
{{{ x = 11 }}}
{{{ y - 3 = (2/5 )*( x + 1 ) }}} 
{{{ y - 3 = (2/5 )*( 11 + 1 ) }}} 
{{{ y - 3 = (2/5)*12 }}}
{{{ y = 24/5 + 3 }}}
{{{ y = 24/5 + 15/5 }}}
{{{ y = 39/5 }}}
Now Do the same with the answer:
{{{ x = (1/2)*( 5y - 17 ) }}}
{{{ 11 = (1/2)*( 5y - 17 ) }}} 
{{{ 22 = 5y - 17 }}}
{{{ 5y = 39 }}}
{{{ y = 39/5 }}}
OK