Let c and i equal the current ages of Christopher and Ishaan.
c=i-20
(i-14)=3(c-14), using c found above in this equation gives you:
i-14=3(i-20-14) which is
i-14=3i-102 add 14 to both sides
i=3i-88 subtract 3i from both sides
-2i=-88 divide both sides by -2
i=44
Ishaan is now 44 years of age.
check...
c=i-20, so c=24
(i-14)=3(c-14) becomes:
(44-14)=3(24-14)
30=3(10)
30=30