Question 1099090
Let {{{ a }}} = Jack's age now
Let {{{ b }}} = Lacy's age now
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(1) {{{ a = 2b }}}
(2) {{{ ( a+7 ) +( b+7 ) = 59 }}}
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Plug (1) into (2)
(2) {{{ ( 2b + 7 ) + ( b + 7 ) = 59 }}}
(2) {{{ 3b + 14 = 59 }}}
(2) {{{ 3b = 45 }}}
(2) {{{ b = 15 }}}
and
(1) {{{ a = 2*15 }}}
(1) {{{ a = 30 }}}
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Jack is 30 and
Lacy is 15
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check:
{{{ ( a + 7 ) + ( b + 7 ) = 59 }}}
{{{ ( 30 + 7 ) + ( 15 + 7 ) = 59 }}}
{{{ 37 + 22 = 59 }}}
{{{ 59 = 59 }}}
OK