Factorise 2x2 - 98
= 2(x2 - 49)
Factorise
=(3x2 - 21x) + (5x - 35)
= 3x(x - 7) + 5(x - 7)
=(3x + 5)(x - 7)
Therefore $\frac{2(x - 7)(x + 7)}{(3x + 5)(x - 7)} \times \frac{(3x + 5)}{(x + 7)}$
By cancelling out the like terms, you get
$\frac{2(x - 7)}{3x + 5}$
raphael answered the question on January 24, 2017 at 06:10
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