Question

please solve and explain it​

Answer 1

Answer:

Here your amswer mark me brainliest

Answer 2

=> a²+ b ² + c ² = 77

=> a+b+c=15 (a+b+c)2 = 152

=> a²+ b²+c²+2 (ab + bc+ca): 225

=> 77 +2 (ab+bc+ca) = 225

=> 2 (ab + bc+ca) = 148

=> ab + bc +ca = 74

Hope it helps :)