Question 1033210
Let {{{ b }}} = Ben's age now
Let {{{ j }}} = Jin's age now
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(1) {{{ b = 3j }}}
(2) {{{ b + 2 = 2*( j + 2 ) }}}
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Substitute (1) into (2)
(2) {{{ 3j + 2 = 2*( j + 2 ) }}}
(2) {{{ 3j + 2 = 2j + 4 }}}
(2) {{{ j = 2 }}}
Jin is 2 now
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check:
(1) {{{ b = 3*2 }}}
(1) {{{ b = 6 }}}
and
(2) {{{ b + 2 = 2*( j + 2 ) }}}
(2) {{{ 6 + 2 = 2*( 2 + 2 ) }}}
(2) {{{ 8 = 2*4 }}}
(2) {{{ 8 = 8 }}}
OK