Question 1138946
Let {{{ t }}} = time in hrs for the 40 mi/hr drive
{{{ t - .5 }}} = time in hrs for the 60 mi/hr drive
Let {{{ d }}} = distance from home to office
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(1) {{{ d = 40t }}}
(2) {{{ d = 60*( t - .5 ) }}}
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(2) {{{ d = 60t - 30 }}}
By substitution:
(2) {{{ 40t = 60t - 30 }}}
(2) {{{ 20t = 30 }}}
(2) {{{ t = 1.5 }}}
and
(1) {{{ d = 40*1.5 }}}
(1) {{{ d = 60 }}}
The distance from home to office is 60 mi
check:
(2) {{{ d = 60*( t - .5 ) }}}
(2) {{{ 60 = 60*( 1.5 - .5 ) }}}
(2) {{{ 60 = 60 }}}
OK