Question 758308
How much of a head start does Lemony get 
in {{{ 3 }}} sec ?
{{{ d[1] = 15*3 }}}
{{{ d[1] = 45 }}} ft
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Start a stopwatch when Carl leaves
Let {{{ t }}} = time in seconds on stopwatch when 
Carl tags Lemony
Let {{{ d }}} = distance in ft that Carl goes until
he catches Lemony
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Equation for lemony:
(1) {{{ d - 45 = 15t }}}
Equation for Carl:
(2) {{{ d = 20t }}}
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By substitution:
(1) {{{ 20t - 45 = 15t }}}
(1) {{{ 5t = 45 }}}
(1) {{{ t = 9 }}}
Carl tags Lemony 9 sec after he leaves safe zone
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check:
(2) {{{ d = 20t }}}
(2) {{{ d = 20*9 }}}
(2) {{{ d = 180 }}} ft
and
(1) {{{ d - 45 = 15t }}}
(1) {{{ d - 45 = 15*9 }}}
(1) {{{ d = 45 + 135 }}}
(1) {{{ d = 180 }}} ft
OK