Question

If a +b+C = 12 and a² +62+
a² + b ² + c²=50, find ab + bc + ca.



please, anyone help me to solve this question, I hv test now​

Answer 1

(a+b+c)^2 = a^2+b^2+c^2+2ab+2bc+2ca (formula)

(a+b+c)^2 = a^2 + b^2+ c^2 + 2(ab+bc+ca)

12^2= 64+2(ab+bc+ca) ( Substituting the given values)

144= 64+2(ab+bc+ ca)

144–64 = 2(ab+bc+ca) (solving)

80= 2(ab+bc+ ca)

80/2 = ab+bc+ca

40 = ab+ bc+ ca

Ans: 40

Answer 2

Answer:

$here \: is \: ur \: answer \: mate \\ given \: a + b + c = 12 \\ then \: ab + bc + ca = \\ a + b + c = 12 \\ by \: squaring \: both \: sides \\ ({a + b + c})^{2} = {12}^{2} \\ {a }^{2} + {b}^{2} + {c}^{2} + 2(ab + bc + ca) = 144 \\ 64 + 2(ab + bc + ca) = 144 \\ 2(ab + bc + ca) = 80 \\ ab + bc + ca \: = 40 \\ hope \: it \: helps \: u$