Question 1006263
Let {{{ a }}} = cost of 1 natural bulb
Let {{{ b }}} = cost of 1 ceiling bulb
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(1) {{{ 5a + 2b = 23 }}}
(2) {{{ 3a + 4b = 25 }}}
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Multiply both sides of (1) by {{{ 2 }}}
and subtract (2) from (1)
(1) {{{ 10a + 4b = 46 }}}
(2) {{{ -3a - 4b = - 25 }}}
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{{{ 7a = 21 }}}
{{{ a = 3 }}}
and
(1) {{{ 5*3 + 2b = 23 }}}
(1) {{{ 15 + 2b = 23 }}}
(1) {{{ 2b = 8 }}}
(1) {{{ b = 4 }}}
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A natural bulb costs $3
A ceiling bulb costs $4