Question

Jivesh also has a more powerful Model B rocket. For this rocket, he uses the equation h=-490t^2+1260t. When is the height of the Model B rocket 810 centimeters? ( it also includes number 19, but I need 20)

Answer 1

Answer:

1.29 s

Step-by-step explanation:

h = -490t² + 1260t

810 = -490t² + 1260t

490t² - 1260t + 810 = 0

49t² - 126t + 81 = 0

(7t - 9)² = 0

7t - 9 = 0

t = 9/7

t ≈ 1.29