Q4 of 59 Page 23

Factorization of x2 + 2x – 8 is

Suppose (x + p)(x + q) are two factors of x2 + 2x – 8.


Then, x2 + 2x – 8 = (x + p)(x + q)


= x2 + (p + q)x + pq


So, to factorize we have to find p and q, such that pq = – 8 and p + q = 2.



∴ x2 + 2x – 8 = (x + 4)(x – 2)

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