Please help will brainlist if right

12. B

13 A

18 B

19 B

Step-by-step explanation:

12. The solutions of the quadratic is the roots, so 0 = x^2 -7x -30 = (x-10)(x+3). For this to be satisfied, either x-10 = 0 -> x = 10 and x + 3 = 0 -> x = -3

13. Either x = 0 or x+8 = 0 -> x =-8 for this to be true

18. The GCF of 2, 6, and 20 is 2. No other number satisfies being a common factor.

19. The product of the solutions of the equation is the (constant/leading coefficient) in the quadratic, which is -8/1 = -8

I 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