Question 1047277

My sister is {{{2}}} years older than I am. 

so, if your age is {{{x}}}, than sister's age is {{{(x+2)}}}

if the sum of your ages is {{{20}}}, than {{{x+(x+2)=20}}}-> solve for {{{x}}}

{{{x+x+2=20}}}

{{{2x=20-2}}}

{{{2x=18}}}

{{{x=18/2}}}

{{{x=9}}}

now find sister's age

 {{{(x+2)=9+2=11}}}

so, your age is {{{9}}} and your sister's age is {{{11}}}