Question

. If (a+b+c)=14 and (a2-b2+c) = 74, then the value of (ab-bc+ca) is​

Answer 1

61

Step-by-step explanation:

(a +b+c)² = a² +b²+c² +2(ab+bc+ca)

14² = 74+2(ab+bc+ca)

196 -74 = 2(ab+bc+ca)

122 = ab+bc+ca

2

61=ab+bc+ca