Question 775271
Let {{{ v }}} = number of video's she bought
Let {{{ c }}} = number of CD's she bought
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(1) {{{ v + c = 6 }}}
(2) {{{ 14.95v + 16.88c = 93.56 }}}
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(2) {{{ 1495v + 1688c = 9356 }}}
Multiply both sides of (1) by {{{ 1495 }}}
and subtract (1) from (2)
(2) {{{ 1495v + 1688c = 9356 }}}
(1) {{{ -1495v - 1495c = -8970 }}}
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{{{ 193c = 386 }}}
{{{ c = 2 }}}
and, since
(1) {{{ v + c = 6 }}}
(1) {{{ v = 6 - 2 }}}
(1) {{{ v = 4 }}}
4 = number of video's she bought
2 = number of CD's she bought
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check:
(2) {{{ 14.95*4 + 16.88*2 = 93.56 }}}
(2) {{{ 59.8 + 33.76 = 93.56 }}}
(2) {{{ 93.56 = 93.56 }}}
OK