Question

what is the anwer of this​

Answer 1

Use the identity

(a+b+c)² = a²+b²+c²+2(ab+bc+ca)

10²=a²+b²+c²+2(19)

On solving we get a²+b²+c² = 62

Answer 2

$\huge{\mathfrak{\blue{\underline{Answer}}}}$

$(a + b + c) {}^{2} = a {}^{2} + b {}^{2} + c {}^{2} + 2ab + 2bc + 2ca \\ (10) {}^{2} = a {}^{2} + b { }^{2} + c {}^{2} + 2(ab + bc + ca) \\ (10) {}^{2} = a {}^{2} + b {}^{2} + c {}^{2} + 2(19) \\ 100 = a {}^{2} + b {}^{2} + c {}^{2} + 38 \\ 100 - 38 = a {}^{2} + b {}^{2} + c {}^{2} \\ 62 = a {}^{2} + b {}^{2} + c {}^{2}$