Question

If a+b = 7, and a² +b²=25
then ab = ?​

Answer 1

a2+b2=25

or, (a+b)^2-2ab=25

or, (7)^2-2ab=25 [a+b=7]

or, 49-25=2ab

or, 24/2=an

•°• ab=12....