Dear Rosabella09: For 9- Two possible dimensions are 8x15 and 10x20.
For 10- 16(8+18)1/2=208 208-(16x8/2)=208-64= [144 squared feet]
<span>There are several ways to find the max of min of a quadratic equation.
Max occurs when t = -b/2a
t = -b/2a = -68/(2*-4.9) = 6.93 second
Max altitude = h(6.93) = 68(6.93)-4.9(6.93^2) = 235.92 meters
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At 08:00 there are 18 bags
At 08:10 there are an extra 10 produced = 28 but 1/2 are consumed leaving 14
At 08:20 there are an extra 10 produced = 24 but 1/2 are consumed leaving 12
At 08:30 there are an extra 10 produced = 22 but 1/2 are consumed leaving 11
At 08:36 another 6 have been produced = 17 bags
Your answer is correct. I think your working is wrong
T is less then or equal to 10 equals 100