Question

if a^2+b^2+c^2=20 and ab+bc+ca=9/2​

Answer 1

Answer:

(a+b+c)²=29

Step-by-step explanation:

(a+b+c)²=a²+b²+c²+2ab+2bc+2ca

(a+b+c)²=a²+b²+c²+2(ab+bc+ac)

(a+b+c)²=20+2(9/2)

(a+b+c)²=20+9

(a+b+c)²=29

Hope u will understand it ......