Question 992951
Let {{{ t }}} = time in hrs for 1st part of trip
(1) {{{ d = 30t }}}
(2) {{{ d = 20*( 5 - t ) }}}
Substitute (1) into (2)
(2) {{{ 30t = 20*( 5-t ) }}}
(2) {{{ 30t = 100 - 20t }}}
(2) {{{ 50t = 100 }}}
(2) {{{ t = 2 }}}
and
(1) {{{ d = 30*2 }}}
(1) {{{ d = 60 }}}
The person can drive 60 mi into country
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check:
(2) {{{ d = 20*( 5 -2 ) }}}
(2) {{{ d = 20*3 }}}
(2) {{{ d = 60 }}}
OK