Question 1156130
Let {{{ a }}} = Jane's age
Let {{{ b }}} = Bob's age
------------------------------
(1) {{{ a = 2b - 18 }}}
(2) {{{ a + b = 63 }}}
----------------------------
Plug (1) into (2)
(2) {{{ 2b - 18 + b = 63 }}}
(2) {{{ 3b = 81 }}}
(2) {{{ b = 27 }}}
----------------------------
(1) {{{ a = 2b - 18 }}}
(1) {{{ a = 2*27 - 18 }}}
(1) {{{ a = 54 - 18 }}}
(1) {{{ a = 36 }}}
----------------------------
Jane is 36
Bob is 27