8X5000 is 40000. There's three zeroes in5000 and no zeroes in 8, yet there are 4 zeroes in the answer. This is because you must multiply the non-zeroes, and then add the zeroes from your factors. 8 times 5 is 40, add 3 zeroes to get 40000.
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The maximum height is 64ft and the ballon is only in the air for 2 seconds
Now, we know that 90°< θ <180°, that simply means the angle θ is in the II quadrant, where sine is positive and cosine is negative.

In order to do this you have to substitute b with 9 and get 3a+9=54, now subtract 9 from both sides to leave a by itself and get 3a=45, now divide 3 in both sides to leave a by itself and get a=15
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