How do you simplify (x^2 +3x)/(2x-14)*(x^2 -49)/(x^2 – 2x -15)#?

1 Answer
Mar 20, 2018

(x(x-7))/(2(x-5))=(x²-7x)/(2x-10)

Explanation:

[0] (x²+3x)/(2x-14)*(x²-49) /(x²-2x-15) first let's multiply.
[1]((x²+3x)(x²-49)) /((2x-14)(x²-2x-15)) , then,
a²-b²=(a-b) (a+b)
[2](x(x+3)(x-7)cancel(x+7))/(2(cancel(x+7)) (x²-2x-15)) now, we see that color(red)(-3 and 5) are trivial roots of (x²-2x-15)
[3] (x(cancel(x+3))(x-7))/(2(cancel(x+3))(x-5))
[4](x(x-7))/(2(x-5))
[5](x²-7x)/(2x-10)