Question

if a²+b²+c² = 20 and ab+bc+ca = 8
find the value of a+b+c.​

Answer 1

Answer:

Given:

a²+b²+c²=20,ab+BC+AC=8

To find:

a+b+c=?

Solution:

(a+b+c)²=a²+b²+c²+2ab+2bc+2ac

(a+b+c)²=20+2(ab+BC+ac)

(a+b+c)²=20+2(8)

(a+b+c)²=20+16

(a+b+c)=36

Taking square root...

√(a+b+c)²=√36

a+b+c=6

Therefore the answer is a+b+c=6