Question 550867
Let {{{ a }}} = tens digit
Let {{{ b }}} = units digit
given:
(1) {{{ a = 3b + 1 }}}
(2) {{{ 10a + b = 3*( 10b + a ) - 9 }}}
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(2) {{{ 10a + b = 30b + 3a - 9 }}}
(2) {{{ 7a - 29b = -9 }}}
Substitute (1) into (2)
(2) {{{ 7*( 3b + 1 ) - 29b = -9 }}}
(2) {{{ 21b + 7 - 29b = -9 }}}
(2) {{{ -8b = -2 }}}
(2) {{{ b = 1/4 }}}
Either I made a mistake, or this is 
impossible to solve. Did you copy it right?