Step-by-step explanation:

Since x-3=0, move the number by x=3 then that means that x=3. And distribute or substitue it into the polynomial.

P(x)= (3)³-7(3)²+11(3)+3

Then simplify;

P(3)=27-7(9)+33+3=0

P(3)=27-63+33+3=0

P(3)= -36+33+3=0

P(3)= -3+3=0

P(3)= 0=0

Therefore, x-3 is a factor of P(x)=x³-7x²+11x+3.