Question 573700
Let {{{c}}} = number of cows
Let {{{m}}} = number of men
given:
(1) {{{ 4c + 2m = 26 }}}
(2) {{{ c + m = 8 }}}
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Multiply both sides of (2) by {{{2}}}
and subtract (2) from (1)
(1) {{{ 4c + 2m = 26 }}}
(2) {{{ -2c - 2m = -16 }}}
{{{ 2c = 10 }}}
{{{ c = 5 }}}
and
(2) {{{ c + m = 8 }}}
(2) {{{ 5 + m = 8 }}}
(2) {{{ m = 3 }}}
There are 3 men and 5 cows
check:
(1) {{{ 4c + 2m = 26 }}}
(1) {{{ 4*5 + 2*3 = 26 }}}
(1) {{{ 20 + 6 = 26 }}}
(1) {{{ 26 = 26 }}}
OK