Question 879835
Let {{{ n }}} = number of children at party
Let {{{ C }}} = total cost of party
At pizza place:
{{{ C = 8n + 30 }}}
At taco place:
{{{ C = 12n + 14 }}}
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Find {{{ n }}} that will make the cost, {{{C }}}
of the 2 places equal
{{{ 8n + 30 = 12n + 14 }}}
{{{ 4n = 16 }}}
{{{ n = 4 }}}
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If 1 more child is invited, the {{{ n = 5 }}}
At pizza place:
{{{ C = 8n + 30 }}}
{{{ C = 8*5 + 30 }}}
{{{ C = 70 }}}
At taco place:
{{{ C = 12n + 14 }}}
{{{ C = 12*5 + 14 }}}
{{{ C = 74 }}}
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When 5 children are invited, the cost becomes less
at the pizza place
Here are plots of the 2 equations:
 {{{ graph( 400, 400, -1, 7, -10, 100, 8x + 30, 12x + 14 ) }}}