A rocket is launched from atop a 95-foot cliff with an initial velocity of 119 ft/s.
a. Substitute the values into the vertical motion formula h = –16t^2 + vt + c. Let h = 0.
b. Use the quadratic formula to find out how long the rocket will take to hit the ground after it is launched. Round to the nearest tenth of a second.
Can you please show how you got the answers so that I can understand it? Thanks.
a. Substitute the values into the vertical motion formula h = –16t^2 + vt + c. Let h = 0.
b. Use the quadratic formula to find out how long the rocket will take to hit the ground after it is launched. Round to the nearest tenth of a second.
Can you please show how you got the answers so that I can understand it? Thanks.
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Ok the quadratic formula is -b +- (square root) b^2 -4ac (end square root)/2a so I like to start out with the -4ac so that would be -4 x -16 x 95 = 6080. Then add that to b^2 (because we already used the minus in the -4) and the equation would be 119^2 or 14161 + 6080 = 20241. Take the square root of that which is 142.27. Now you have -b +- 142.27/2a. So that is -119 +- 142.27/-32. Now you have all numbers and solve. -119 + 142.27 = 23.27. 23.27/-32 is -.73. -119 - 142.27 is -261.27. -261.27/-32 = 8.16. So your two answers are -.73 and 8.16 and since its impossible to have negative time for the rocket to hit the ground your only answer is 8.16.
A = 0 = -16t^2 + 119t + 95
B = 8.16 seconds (It says round to nearest tenth so it would be 8.2 seconds). Good luck!
I am an eighth grader in Algebra and we recently learned this.
A = 0 = -16t^2 + 119t + 95
B = 8.16 seconds (It says round to nearest tenth so it would be 8.2 seconds). Good luck!
I am an eighth grader in Algebra and we recently learned this.