Question

daca a+b=8 si a²+b²=44 aflati a*b=?

Answer 1

$a+b=8\Rightarrow (a+b)^2=64\Rightarrow a^2+2ab+b^2=64\Rightarrow 44+2ab=64\Rightarrow$

$\Rightarrow 2ab=20\rightarrow ab=10.$