Question

if a+b=7 and ab=12, then find the value of a²-ab+b².

Answer 1

13 is the answer when a=3 & b=4

Answer 2

a^2+b^2=(a+b)^2-2ab
=(7) ^2-2*12
=49-24
a^2+b^2 =25

Now a^2-ab+b^2
=25-12 (a^2+b^2 = 25)
and (ab=12)

=13