Question 644306
Let {{{ a }}} = Jim's age now
Let {{{ b }}} = Joe's age now
given:
(1) {{{ a + 2 = 2*( b + 2 ) }}}
(2) {{{ a - 10 = 5*( b - 10 ) }}}
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(1) {{{ a + 2 = 2b + 4 }}}
(1) {{{ a - 2b = 2 }}}
and
(2) {{{ a - 10 = 5b - 50 }}}
(2) {{{ -a + 5b = 40 }}}
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Add the equations
{{{ 3b = 42 }}}
{{{ b = 14 }}}
and, since
(1) {{{ a - 2*14 = 2 }}}
(1) {{{ a - 28 = 2 }}}
(1) {{{ a = 30 }}}
Jim is 30 now
Joe is 14 now
check:
(2) {{{ -a + 5b = 40 }}}
(2) {{{ -30 + 5*14 = 40 }}}
(2) {{{ -30 + 70 = 40 }}}
(2) {{{ 40 = 40 }}}
OK