Q1 of 27 Page 90

The product of a number and 2 more than that is 168. What are the numbers?

Let the number be x.

Now, According to the question


(x)(x + 2) = 168


= x2 + 2x = 168


= x2 + 2x – 168 = 0


It’s a second degree equation.


and we can use splitting the middle term method.


= x2 + 14x – 12x – 168 = 0


= x(x + 14) – 12(x + 14) = 0


= (x–12) (x + 14)


There could be two values of x which are 12 and –14.


and the two number in each case would be (12,14) and (–14,–12).


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