Question 1090309


let my age be {{{x}}}, and the age of my sister {{{y}}}

if I am {{{6}}} years older than my sister, we have

{{{x=y+6}}}.....eq.1

if the sum of our ages is {{{24}}} years, we have 

{{{x+y=24}}}..........eq.2 substitute {{{x}}} from eq.1

{{{y+6+y=24}}}...solve for {{{y}}}

{{{2y=24-6}}}

{{{2y=18}}}

{{{y=9}}}->  my sister is {{{9}}} years old


{{{x=y+6}}}.....eq.1 substitute {{{y}}}

{{{x=9+6}}}

{{{x=15}}}-> I am {{{15}}} years old