Question 557992
Let {{{ d }}} = the distance to the repair yard in miles
Let {{{ t }}} = the time to get back in hours
given:
Going to repair yard:
(1) {{{ d = 54*( t - 1 ) }}}
Coming back:
(2) {{{ d = 45t }}}
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Substitute (2) into (1)
(1) {{{ 45t = 54*( t - 1 ) }}}
(1) {{{ 45t = 54t - 54 }}}
(1) {{{ 54t - 45t = 54 }}}
(1) {{{ 9t = 54 }}}
(1) {{{ t = 6 }}}
{{{ t - 1 = 5 }}}
The trip to the repair yard took 5 hrs
check answer:
(1) {{{ d = 54*( t - 1 ) }}}
(1) {{{ d = 54*5 }}}
(1) {{{ d = 270 }}}
and
(2) {{{ d = 45t }}}
(2) {{{ d = 45*6 }}}
(2) {{{ d = 270 }}} 
OK