Question

If a +b+c=35 and ab + bc + ca = 23 find a+b+c.

± 9

±8
what will be the answer+8 or +9

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Answer 1

Step-by-step explanation:

option a :+9 ........ .......

Answer 2

(a+b+c)²=a²+b²+c²+2(ab+bc+ca)

(a+b+c)²=35+2(23)

(a+b+c)²=81

a+b+c=√81

a+b+c=±9

hope it helps