Question

If a-2b = 15 and find a²+ 4b² .

Answer 1

I think thts question is not valid as it has not given ab
however i will tell you how to solve this if ab was given
as a-2b = 15 square both lhs and rhs
a^2-4ab+b^2=15^2
a^2+4b^2=225+4ab
substituting the value of ab u will get the answer

THANK YOU