Question 976548
Let {{{ a }}} = Pat's age now
Let {{{ b }}} = his son's age now
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(1) {{{ a = b + 17 }}}
(2) {{{ a + 5 = 2*( b + 5 ) }}}
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(2) {{{ a + 5 = 2b + 10 }}}
(2) {{{ a - 2b = 5 }}}
and
(1) {{{ a - b = 17 }}}
Subtract (2) from (1)
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(1) {{{ a - b = 17 }}}
(2) {{{ -a + 2b = -5 }}}
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{{{ b = 12 }}}
and
(1) {{{ a = b + 17 }}}
(1) {{{ a = 12 + 17 }}}
(1) {{{ a = 29 }}}
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Pat is 29
His son is 12
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check:
(2) {{{ a + 5 = 2*( b + 5 ) }}}
(2) {{{ 29 + 5 = 2*( 12 + 5 ) }}}
(2) {{{ 34 = 2*17 }}}
(2) {{{ 34 = 34 }}}
OK