Question 1084582
Let {{{ x }}} = number of hamburgers
Let {{{ y }}} = number of cheeseburgers
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(1) {{{ x + y = 352 }}}
(2) {{{ y = 3x }}}
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Substitute (2) into (1)
(1) {{{ x + 3x = 352 }}}
(1) {{{ 4x = 352 }}}
(1) {{{ x = 88 }}}
and
(2) {{{ y = 3x }}}
(2) {{{ y = 3*88 }}}
(2) {{{ y = 264 }}}
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88 hamburgers were sold
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check:
(1) {{{ x + y = 352 }}}
(1) {{{ 88 + 264 = 352 }}}
(1) {{{ 352 = 352 }}}
OK