Question 943759
Let {{{ a }}} = Jack's age now
Let {{{ b }}} = Jill's age now
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(1) {{{ a = 2b }}}
(2) {{{ a + 2 = 4*( b - 9 ) }}}
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(2) {{{ a + 2 = 4b - 36 }}}
By substitution:
(2) {{{ 2b + 2 = 4b -  36 }}}
(2) {{{ 2b = 38 }}}
(2) {{{ b = 19 }}}
and
(1) {{{ a = 2b }}}
(1) {{{ a = 2*19 }}}
(1) {{{ a = 38 }}}
Jack is 38
Jill is 19
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check:
(2) {{{ a + 2 = 4*( b - 9 ) }}}
(2) {{{ 38 + 2 = 4*( 19 - 9 ) }}}
(2) {{{ 40 = 4*10 }}}
(2) {{{ 40 = 40 }}}
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I think this is it. Work on your typing
It was terrible