Question 1123958
Let {{{ t }}} = time in minutes to go up the tree
{{{ 3 - t }}} = time in minutes to go down the tree
Let {{{ h }}} = the height of the tree in feet
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Equation for going up:
(1) {{{ h = 10t }}}
Equation for going down:
(2) {{{ h = 20*( 3 - t ) }}}
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By substitution:
(2) {{{ 10t = 20*( 3 - t ) }}}
(2) {{{ 10t = 60 - 20t }}}
(2) {{{ 30t = 60 }}}
(2) {{{ t = 2 }}}
And
(1) {{{ h = 10*2 }}}
(1) {{{ h = 20 }}}
The tree is 20 ft high
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Check:
(2) {{{ h = 20*( 3 - 2 ) }}}
(2) {{{ h = 20 }}}
OK