Question 844309
Let the number be {{{ a }}} and {{{ b }}}
and assume {{{ b }}} is the larger
given:
(1) {{{ a + b  = 3 }}}
(2) {{{ 4b + 3a = 25 }}}
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Multiply both sides of (1) by {{{ 3 }}}
and subtract (1) from (2)
(2) {{{ 3a + 4b = 25 }}}
(1) {{{ -3a - 3b = -9 }}}
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{{{ b = 16 }}}
and
(1) {{{ a + b  = 3 }}}
(1) {{{ a + 16  = 3 }}}
(1) {{{ a = -13 }}}
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{{{ a = -13 }}}
{{{ b = 16 }}}
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check:
(2) {{{ 4b + 3a = 25 }}}
(2) {{{ 4*16 + 3*(-13) = 25 }}}
(2) {{{ 64 - 39 = 25 }}}
(2) {{{ 25 = 25 }}}
OK