Question 935619
Let {{{ j }}} = John's age now
Let {{{ a }}} = Alexis's age now
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(1) {{{ j = 2a }}}
(2) {{{ j - 6 = 5*( a- 6 ) }}}
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Substitute (1) into (2)
(2) {{{ 2a - 6 = 5*( a-6 ) }}}
(2) {{{ 2a - 6 = 5a - 30 }}}
(2) {{{ 5a - 2a = 30 - 6 }}}
(2) {{{ 3a = 24 }}}
(2) {{{ a = 8 }}}
and, since
(1) {{{ j = 2a }}}
(1) {{{ j = 16 }}}
John is 16 now
check:
(2) {{{ j - 6 = 5*( a - 6 ) }}}
(2) {{{ 16 - 6 = 5*( 8 - 6 ) }}}
(2) {{{ 10 = 5*2 }}}
(2) {{{ 10 = 10 }}}
OK