Question 1099915
Let {{{ C }}} = cost in dollars of {{{ n }}} tablets
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(a)
Use the general point-slope formula
{{{ ( C - 23.5 ) / ( n - 2 ) = ( 58.75 - 23.5 ) / ( 5 - 2 ) }}}
{{{ ( C - 23.5 ) / ( n - 2 ) = 35.25 / 3 }}}
{{{ ( C - 23.5 ) / ( n - 2 ) = 11.75 }}}
Multiply both sides by {{{  n - 2 }}}
{{{ C - 23.5  = 11.75*( n - 2 ) }}}
{{{ C - 23.5 =  11.75n - 23.5 }}}
{{{ C = 11.75n }}}
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(b)
{{{ n = 14 }}}
{{{ C = 11.75*14 }}}
{{{ C = 164.5 }}}
$164.50
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check the equation:
Does it go through ( 2, 23.5 ) ?
{{{ C = 11.75n }}}
{{{ 23.5 = 11.75*2 }}}
{{{ 23.5 = 23.5 }}}
and
Does it go through ( 5, 58.75 ) ?
{{{ 58.75 = 11.75*5 }}}
{{{ 58.75 = 58.75 }}}
OK