Question 1092865
Let {{{ a }}} = number of red roses
Let {{{ b }}} = number of yellow roses
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(1) {{{ a + b = 12 }}}
(2) {{{ 3.5a + 5.5b = 52 }}}
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Multiply both sides of (1) by {{{ 3.5 }}}
and subtract (1) from (2)
(2) {{{ 3.5a + 5.5b = 52 }}}
(1) {{{ -3.5a - 3.5b = -42 }}}
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{{{ 2b = 10 }}}
{{{ b = 5 }}}
and
(1) {{{ a + 5 = 12 }}}
(1) {{{ a = 7 }}}
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7 red roses
5 yellow roses