Question

Fie ecuatia x patrat -ax+20. Daca 4 este solutie a ecuatiei atunci calculati media geometrica a solutiilor ecuatiei date

Answer 1

$4^{2} -a*4+20=0$
16-4a+20=0
4a=20+16
4a=36
a=36/4=9
x∧2-9x+20=0
x∧2-4x-5x+20=0
x(x-4)-5(x-4)=0
(x-4)(x-5)=0⇒x=4 si x=5
m=$\sqrt{4*5} =2 \sqrt{5}$