Question

if a+b+c=9 and ab+bc+cn=23, then a^2+b^2+c^2 ?
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Answer 1

CORRECT QUESTION:

If a+b+c=9 and ab+bc+ca=23, then a²+b²+c²=?

ANSWER:

a²+b²+c²=35

GIVEN:

a+b+c=9

ab+bc+ca=23

FORMULA:

(a+b+c)²=a²+b²+c²+2ab+2bc+2ca

EXPLANATION:

(a+b+c)²=a²+b²+c²+2(ab+bc+ca)

SUBSTITUTE:a+b+c=9 and ab+bc+ca=23

9²=a²+b²+c²+2(23)

a²+b²+c²=81-46

a²+b²+c²=35

THE VALUE OF a²+b²+c²=35.