How do you factor x³-9?

(x² + 3)(x-3)

Step-by-step explanation:

Since the exponent is uneven you can take 2 and 1 and add them to the x's multiply to get 3 and since 9 is a perfect square you can square root it and get 3 which you put on both sides. Since the 9 is negative one of the symbols have to be negative, usually put in the second parenthesis.

Hope this helps!

54 km / hours

step-by-step explanation:

we need to convert seconds to hours

60 seconds = 1 minutes

60 minutes = 1hour

15 m         60 second   60 minutes

  * *         = 54000 meters/ hour

second     1 minute             1 hour

now we need to convert meters to km

1000 m = 1 km

54000 m       1 km

*   = 54 km / hours

hour               1000m