SOLUTION: A Rock is launched from a cannon. Its height, h(x), can be represented by a quadratic function in terms of time, x, in seconds. After 1 second, the rock is 129 feet in the air; af

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Question 970768: A Rock is launched from a cannon. Its height, h(x), can be represented by a quadratic function in terms of time, x, in seconds.
After 1 second, the rock is 129 feet in the air; after 2 seconds it is 236 feet in the air.
Find the height, in feet, of the rock after 5 seconds in the air.
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
A possible good model for this can be h%28x%29=a%2Ax%5E2.

x_______h
1______129
2______236

system%28a%2A1%5E2=129%2Ca%2A2%5E2=236%29

a=129%2C4a=236
a=59
Not consistent.

Try another model: h=ax%5E2%2Bk
system%28a%2A1%5E2%2Bk=129%2Ca%2A2%5E2%2Bk=236%29
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system%28a%2Bk=129%2C4a%2Bk=236%29
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This one will give highlight%28a=107%2F3%29 and this can be used in either equation to evaluate k.