Question 166050
call Dylan=d
:    Krista=k


so {{{d+k=25}}} and   {{{d+12=4(k-5)+7}}}
:  {{{d=25-k}}} and   {{{d+12=4k-20+7}}}  simplifying
:  {{{(25-k)+12=4k-13}}}substituting d value in first equation into 2nd equation

:  {{{37-k=4k-13}}} combining terms {{{5k=50}}} divide by 5  {{{k=10}}}

now {{{d=25-k(10)=15}}}