Question 1035180
(1) {{{ (2/5)*x + (3/4)*y = 5/2 }}}
(2) {{{ (-2/3)*x + (1/2)*y = 3/4 }}}
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Multiply both sides of (1) by {{{ 20 }}}
Multiply both sides of (2) by {{{ 12 }}}
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(1) {{{ 8x + 15y = 50 }}}
(2) {{{ -8x + 6y = 9 }}}
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Add the equations
{{{ 21y = 59 }}}
{{{ y = 59/21 }}}
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and
(2) {{{ -8x + 6*( 59/21 ) = 9 }}}
(2) {{{ 8x = 118/7 - 63/7 }}}
(2) {{{ 8x = 55/7 }}}
(2) {{{ x = 55/56 }}}
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check the answers:
(1) {{{ (2/5)*x + (3/4)*y = 5/2 }}}
(1) {{{ (2/5)*(55/56) + (3/4)*(59/21) = 5/2 }}}
(1) {{{ 22/56 + 59/28 = 5/2 }}}
(1) {{{ 22/56 + 118/56 = 140/56 }}}
(1) {{{ 140/56 = 140/56 }}}
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You can check (2)