Step 1 :We are given a ball thrown from a height of 49 meters with an initial downward velocity of 2 m/s. The height of the ball after t seconds is given by the equation \(h=49-2t-5t^2\).
Step 2 :We need to find the time when the ball hits the ground, which is when the height h is zero. So, we need to solve the equation \(49-2t-5t^2 = 0\) for t.
Step 3 :This is a quadratic equation in the form \(at^2 + bt + c = 0\), where \(a = -5\), \(b = -2\), and \(c = 49\).
Step 4 :The solutions to this equation are given by the quadratic formula \(t = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}\).
Step 5 :Substituting the values of a, b, and c into the quadratic formula, we get two solutions for t: \(t1 = -3.3368774282716247\) and \(t2 = 2.9368774282716243\).
Step 6 :Since time cannot be negative, we discard the negative solution and take \(t = 2.9368774282716243\).
Step 7 :Rounding to the nearest hundredth, we get \(t = 2.94\) seconds.
Step 8 :Final Answer: The ball hits the ground approximately \(\boxed{2.94}\) seconds after it is thrown.