Question 1041234
Let {{{ a }}} = number of large frames she bought
Let {{{ b }}} = number of small frames she bought
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(1) {{{ a + b = 27 }}}
(2) {{{ 14a + 7b = 245 }}}
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There are 2 equations and 2 unknowns
so it's solvable
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Multiply both sides of (1) by {{{ 7 }}}
and subtract (1) from (2)
(2) {{{ 14a + 7b = 245 }}}
(1) {{{ -7a - 7b = -189 }}}
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{{{ 7a = 56 }}}
{{{ a = 8 }}}
and
(1) {{{ a + b = 27 }}}
(1) {{{ 8 + b = 27 }}}
(1) {{{ b = 19 }}}
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She bought 8 large frames and 19 small frames
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check:
(2) {{{ 14a + 7b = 245 }}}
(2) {{{ 14*8 + 7*19 = 245 }}}
(2) {{{ 112 + 133 = 245 }}}
(2) {{{ 245 = 245 }}}
OK