Question

If a+b+c=7 and a2+b2+32=45 find the value of ab+bc+ca

Answer 1

Answer:

ab +bc +ca = 2

Step-by-step explanation:

a + b + c = 7

a² + b² + c² = 45

a + b + c = 7

(a+b+c)² = 7²

a² + b² + c² +2ab +2bc +2ca = 49

45 + 2(ab +bc +ca) = 49

2(ab +bc +ca) = 49 -45

ab +bc +ca = 4/2

ab +bc +ca = 2