Question 979080
(1) {{{ s = 3t }}}
(2) {{{ s + 4 = 2*( t + 4 ) }}}
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Substitute (1) into (2)
(2) {{{ 3t + 4 = 2t + 8 }}}
(2) {{{ t = 4 }}}
and
(1) {{{ s = 3t }}}
(1) {{{ s = 3*4 }}}
(1) {{{ s = 12 }}}
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Sandy is 12 now
check:
(2) {{{ s + 4 = 2*( t + 4 ) }}}
(2) {{{ 12 + 4 = 2*( 4 + 4 ) }}}
(2) {{{ 16 = 2*8 }}}
(2) {{{ 16 = 16 }}}
OK