It cannot be 30, because the sum of two sides should be more than third side
-not D
10+18=28 <30
it cannot be 6 +10 < 18
it cannot 8
8+10=18
so it is has to be C) 12
12+18>10
10+12>18
10+18>12
answer C. 12 cm
13
14=2•7
15=3•5
16=2•2•2•2
17
18=2•3•3
19
20=2•2•5
...
34+0+18+26
34+18+26
52+26
78
The sum is 78
Given that the height of the disc is modeled by the function:
h=-16t^2+20t+6
a] The maximum height will be as follows:
At maximum height:
h'(t)=0
from h(t)
h'(t)=-32t+20=0
thus
t=20/32
t=5/8 sec
thus the maximum height will be:
h(5/8)=-16(5/8)^2+20(5/8)+6
=12.25 ft
b] <span>How long will it take the disc to reach the maximum height?
</span>time taken to reach maximum height will be:
from h(t)
h'(t)=-32t+20=0
thus
t=20/32
t=5/8 sec
thus time taken to reach maximum height is t=5/8 sec
c]<span>How long does it take for the disc to be caught 3 feet off the ground?
</span>h(t)=-16t^2+20t+6
but
h(t)=3
thus
3=-16t^2+20t+6
solving for t we get:
0=-16t^2+20t+3
factoring the above we get:
t=5/8-/+√37/8
t=-1.5256 or 2.776
since there is no negative time we pick t=2.776
Hence time taken for the disc to be caught 3 ft from the ground is 2.776 ft
