Question 1154044
Let {{{ a }}} = Jessy's age
Let {{{ b }}} = Carmen's age
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(1) {{{ a + b = 52 }}}
(2) {{{ a = 3b - 4 }}}
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(2) {{{ -a + 3b = 4 }}}
(1) {{{ a + b = 52 }}}
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Add (1) and (2)
{{{ 4b = 56 }}}
{{{ b = 14 }}}
and
(1) {{{ a + b = 52 }}}
(1) {{{ a + 14 = 52 }}}
(1) {{{ a = 38 }}}
Jessy is 38
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check:
(1) {{{ a + b = 52 }}}
(1) {{{ 38 + b = 52 }}}
(1) {{{ b = 14 }}}
OK
(2) {{{ a = 3b - 4 }}}
(2) {{{ 38 = 3*14 - 4 }}}
(2) {{{ 38 = 42 - 4 }}}
(2) {{{ 38 = 38 }}}
OK