Question 116914
X^2-5X-14 
YOU NEED TO FIND TWO FACTORS OF -14 THAT WHEN ADDED WILL EQUAL -5.
THE FACTORS OF -14 ARE 1*-14, -1*14, 2*-7 & -2*7
THE FIRST SET ADDS UP TO 1-14=-13
THE SECOND SET ADDS UP TO -1+14=13
THE NEXT SET ADDS UP TO 2-7=-5 THIS LOOKS LIKE A SOLUTION SO WE USE THEM:
(X+2)(X-7) ANSWER.
PROOF
X+2
X-7 NOW MULTIPLY
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X^2+2X-7X-14
X^2-5X-14 
LOOKS LIKE A WINNER TO ME.