if a²+b²+c² = 20 and ab+bc+ca = 8
find the value of a+b+c.
Answers
Answered by
19
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
Similar questions