Question 1047182
Let {{{ d }}} = distance in miles Yolando drives
Let {{{ C }}} = the cost of either plan in dollars
Cost of the 1st plan:
(1) {{{ C = 70 + .3d }}}
Cost of the 2nd plan:
(2) {{{ C = .8d }}}
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Set the costs of the 2 plans equal to eachother
{{{ .8d = 70 + .3d }}}
{{{ .5d = 70 }}}
{{{ d = 140 }}} mi
She has to drive 140 mi for the 2 plans to be the same
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check answer:
(1) {{{ C = 70 + .3d }}}
(1) {{{ C = 70 + .3*140 }}}
(1) {{{ C = 70 + 42 }}}
(1) {{{ C = 112 }}}
and
(2) {{{ C = .8d }}}
(2) {{{ C = .8*140 }}}
(2) {{{ C = 112 }}}
OK