Question 1203280
Father,  51
Son, 19


x how many year ago
{{{(51-x)/(19-x)=5}}}



{{{51-x=5*19-5x}}}

{{{5x-x=5*19-51}}}

{{{4x=95-51}}}
{{{4x=44}}}

{{{highlight(x=11)}}}----------eleven years ago