Question 860090
{{{ 2^y = 16^( x-3 ) }}}
{{{ 2^y = ( 2^4 )^(x-3 ) }}}
{{{ 2^y = 2^( 4*( x-3 ) ) }}}
{{{ y = 4*( x-3 ) }}}
(1) {{{ 4x - y = 12 }}}
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{{{ 3^( y+2 ) = 27^x }}}
{{{ 3^( y+2 ) = ( 3^3 )^x }}}
{{{ 3^( y+2 ) = 3^3x }}}
{{{ y + 2 = 3x }}}
(2) {{{ 3x - y = 2 }}}
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Subtract (2) from (1)
(1) {{{ 4x - y = 12 }}}
(2) {{{ -3x + y = -2 }}}
{{{ x = 10 }}}
and
(2) {{{ 3*10 - y = 2 }}}
(2) {{{ 30 - y = 2 }}}
(2) {{{ y = 28 }}}
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check:
{{{ 2^y = 16^( x-3 ) }}}
{{{ 2^28 = 16^7 }}}
{{{ 2^28 = ( 2^4 )^7 }}}
{{{ 2^28 = 2^28 }}}
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You can check other equation