Question

Q 8. If a +b+c= 19 and ab + bc + ca = -13 then find the value of a²+b²+c² Answer: A. 300 B. 387 C. 357 D. 587 ​

Answer 1

Answer:

Step-by-step explanation:

a+b+c = 19.

ab+bc+ac = -13.

(a+b+c)^2 = a^2 + b^2 + c^2 + 2(ab+bc+ac).

(19)^2 =  a^2 + b^2 + c^2 +2(-13).

361 =  a^2 + b^2 + c^2  + -26.

a^2 + b^2 + c^2  = 361+26

a^2 + b^2 + c^2  = 387.

Hope it helps.