Question 243133
Mother Age = M Daughter Age = D

{{{M/D = 2 + 5/D}}} which is the same as {{{M/D = (2D+5)/D}}}
{{{M = 2D+5}}} (1)
{{{M-5 = 3(D-5)}}} 
{{{M-5 = 3D-15}}} (2)

Subsitute (1) into (2)

{{{(2D+5)-5 = 3D-15}}} 
Rearrange to find D
{{{2D = 3D-15}}}
{{{15 = D}}}

So the daughter is 15 and the mother is 35.