Question

find a zero of the polynamial p(x)=3x+1

Answer 1

3x+1=0

3x=-1

x=-1/3

is your answer

Answer 2

Zero of the polynomial is -1/3
Since p(X)=3x+1 if u put -1/3in place of x it becomes p(X)=3(-1/3)+1= -1 + 1= 0
So hope it helps
And thanks for asking doubt