Answer:
t = 2secs
Step-by-step explanation:
Given the height above the surface expressed as h = -16t^2 + 64 t + 80.
The velocity of the rocket at its maximum height is zero. Hence;
v(t) = dy/dt = 0
dy/dt = -32t + 64
0 = -32t + 64
32t = 64
t = 64/32
t = 2secs
Hence the rocket will hit the lake after 2 secs
 
        
             
        
        
        
Answer:
Step-by-step explanation:
12.718 units
Step-by-step explanation:
The coordinates of the vertices of parallelogram WXYZ are given to be W(0,-1), X(4,0), Y(3,-2) and Z(-1,-3).
So, the perimeter of the parallelogram will be 2(WX + XY) {Since opposite sides of parallelogram are same in length}
Now, length of WX =  units,  To find the units click this link :
https://tex.z-dn.net/?f=%5Csqrt%7B(-1)%5E%7B2%7D%20%2B%204%5E%7B2%7D%20%7D%20%3D%20%5Csqrt%7B17%7D%20%3D%204.123
And, length of XY =  units, To find the units click this link :
https://tex.z-dn.net/?f=%5Csqrt%7B(4-3)%5E%7B2%7D%20%2B%20(0-(-2))%5E%7B2%7D%7D%20%3D%20%5Csqrt%7B5%7D%20%3D%202.236
Therefore, the perimeter of the parallelogram WXYZ = 2(4.123 + 2.236) = 12.718 units. (Answer)
 
        
             
        
        
        
The answer is 68°
step by step :
        
                    
             
        
        
        
Excuse my awful triangle drawing skills, haha.. 
So essentially you need to find the perimeter which is done by adding the lengths of the sides.. this gives you 22ft. 
Then for part b you need to convert 22ft to yards which gives you 7.3 yards. 
Since you can only buy a whole number of yards, you'll actually need 8 yards. 
So if the boarder is $8.75 per yard, and you need 8 yards, how much would it cost? 
Hope this was helpful.
 
        
        
        
You draw perpendicular bisectors to find the center of a circle circumscribed about a triangle. Hook me up with 5 stars :)