Question 854664
Let {{{ m }}} = Matt's age now
Let {{{ n }}} = Neth's age now
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(1) {{{ m - 3 = (1/2)*( n - 3 ) }}}
(2) {{{ m + n = 21 }}}
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(1) {{{ 2*( m - 3 ) = n - 3 }}}
(1) {{{ 2m - 6 = n - 3 }}}
(1) {{{ 2m - n = 3 }}}
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Add (1) and (2)
(2) {{{ m + n = 21 }}}
(1) {{{ 2m - n = 3 }}}
{{{ 3m = 24 }}}
{{{ m = 8 }}}
and
(2) {{{ m + n = 21 }}}
(2) {{{ 8 + n = 21 }}}
(2) {{{ n = 13 }}}
Matt is 8
Neth is 13
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check:
(1) {{{ m - 3 = (1/2)*( n - 3 ) }}}
(1) {{{ 8 - 3 = (1/2)*( 13 - 3 ) }}}
(1) {{{ 5 = (1/2)*10 }}}
(1) {{{ 10 = 10 }}}
OK