Factorize each of the following quadratic polynomials by using the method of completing;
a2 – 14a – 51
Coefficient of a2 = 1
Therefore, we have
a2 – 14a – 51 = a2 – 14a + 72 – 72 – 51 (Therefore, adding and subtracting 72)
= (a – 7)2 – 102 (Completing the square)
= (a – 7 + 10) (9 – 7 – 10)
= (a + 3) (a – 17)
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