Question 1026093
Let {{{ d }}} = the distance in miles  Brenda travels 
after 7.5 hrs
{{{ d + 292.5 }}} = the distance in miles  Jim travels 
after 7.5 hrs
Let {{{ s }}} = Brenda's speed in mi/hr
{{{ 2s - 5 }}} = Jim's speed in mi/hr
------------------------------
Brenda's equation:
(1) {{{ d = s*7.5 }}}
Jim's equation:
(2) {{{ d + 292.5 = ( 2s - 5 )*7.5 }}}
------------------------------
Substitute (1) into (2)
(2) {{{ s*7.5 + 292.5 = ( 2s - 5 )*7.5 }}}
(2) {{{ 7.5s + 292.5 = 15s - 37.5 }}}
(2) {{{ 7.5s = 292.5 + 37.5 }}}
(2) {{{ 7.5s = 330 }}}
(2) {{{ s = 44 }}}
and
{{{ 2s - 5 = 2*44 - 5 }}}
{{{ 2s - 5 = 83 }}}
Brenda's speed is 44 mi/hr
Jim's speed is 83 mi/hr
-------------------
check:
(1) {{{ d = s*7.5 }}}
(1) {{{ d = 44*7.5 }}}
(1) {{{ d = 330 }}}
and
(2) {{{ d + 292.5 = ( 2s - 5 )*7.5 }}}
(2) {{{ d + 292.5 = ( 2*44 - 5 )*7.5 }}}
(2) {{{ d = 83*7.5 - 292.5 }}}
(2) {{{ d = 622.5 - 292.5 }}}
(2) {{{ d = 330 }}}
OK