Question

plz try to answer fast i will mark brainliest answer briefly​

Answer 1

Answer:

±6.

Step-by-step explanation:

(a+b+ c)²= a²+ b² +c² + 2ab + 2bc + 2ac

             = 20+ 2(ab+bc+ac)

             = 20+ 2(8)

             = 20+ 16

             = 36

(a+b+c)² = 36

a+b+c= √36

a+b+c = ±6.

Hope this answer helps.

Please mark me as the brainliest..........

Answer 2

Answer:

(a+b+c)²=36

a+b+c=√36

=6