Question

Question 30 :-
If x+ y+ z= 10 and x y+ y z +z x=30, then find value of x2 +y2 +z2
a. 100
(b) 400
(c) 40
(d) 300.

Plz help me to solve this​

Answer 1

Step-by-step explanation:

Using identity

(a+b+c)²=a²+b²+c²+2(ab+BC+CA)

(10)²=x²+y²+z²+2(30)

100=x²+y²+z²+60

40=x²+y²+z²