<PRE><B>Question 30341</B>
Which of the following is a factor of the polynomial x^2 - x - 20? 
THERE ARE 2 METHODS
1 FACTORISE AND CHECK..F(X)=X^2-X-20=X^2-5X+4X-20=X(X-5)+4(X-5)=(X-5)(X+4)
SO...A...X-5 IS THE ANSWER.
2...PUT X=5,4,-2..ETC..AS PER THE ANSWERS AND CHECK WHEN FUNCTION F(X) BECOMES ZERO..WE SEE THAT F(5)=0..SO X-5 IS A FACTOR.
A) x-5
B) x-4
C) x+2
D) x+5
E) x+10 
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