Question 907189
(1) {{{ 5x - 3y = 15 }}}
(2) {{{ 2x - y = 4 }}}
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{{{ 3y = 5x - 15 }}}
(1) {{{ y = (5/3)*x - 5 }}}
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(2) {{{ y = 2x - 4 }}}
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Here are the plots:
{{{ graph( 400, 400, -10, 5, -15, 5, (5/3)*x - 5, 2x - 4 ) }}}
My guess for the solution
is ( -3, -10 )
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check:
Multiply both sides of (2) by {{{ 3 }}}
and subtract (2) from (1)
(1) {{{ 5x - 3y = 15 }}}
(2) {{{ -6x + 3y = -12 }}}
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{{{ -x = 3 }}}
{{{ x = -3 }}}
and
(1) {{{ 5x - 3y = 15 }}}
(1) {{{ 5*(-3) - 3y = 15 }}}
(1) {{{ -15 - 3y = 15 }}}
(1) {{{ 3y = -30 }}}
(1) {{{ y = -10 }}}
( -3, -10 ) 
OK