Step-by-step explanation:
first of all, your teacher wrote nonsense in the answer options : an area is always given in squared units. never in cubed units (which would be volume).
the area is : 1/2 × perimeter × apothem
the perimeter is simply 12 × 5 = 60 meters.
apothem = (a/2)×cot(pi/12) = 5/2 × cot(pi/12) =
 = 9.330127019... meters
so the area is
1/2 × 60 × 9.330127019... = 279.9038106... m²
therefore, the third answer option is correct (although it is m², and not m³).
by the way, you have question 3 wrong. I answered this with the correct apothem calculation in the explanation for question 4.
 
        
             
        
        
        
2 I 1  6   -16
   I      2    16
   --------------------
      1  8    0
so the quotient is x+8. A is the answer.
        
                    
             
        
        
        
Answer: 27.5 pages per hour
Step-by-step explanation:
Well, first you make the 12 minutes into an hour (times by 5), then times the pages she read (5.5) by 5, which is 27.5, so she reads 27.5 pages per hour, you can also use 27 and a half pages per hour.
 
        
                    
             
        
        
        
Answer:
True
Step-by-step explanation:
We can plug in and see.
If (3,0) is on the graph of P, then P(3) will evaluate to 0.
Let's try it:
P(3)=(3)^3-7(3)^2+15(3)-9
P(3)=27-7(9)+45-9
P(3)=27-63+45-9
P(3)=-36+45-9
P(3)=9-9
P(3)=0
Since P(3)=0, then (3,0) is an ordered pair of P.
 
        
             
        
        
        
Sin³ x-sin x=cos ² x
we know that:
sin²x + cos²x=1  ⇒cos²x=1-sin²x
Therefore:
sin³x-sin x=1-sin²x
sin³x+sin²x-sin x-1=0
sin³x=z
z³+z²-z-1=0
we divide by Ruffini method:
              1     1     -1     -1
        1           1      2      1                z=1
-------------------------------------
              1     2      1      0
       -1         -1      -1                       z=-1
--------------------------------------
              1     1       0                       z=-1
Therefore; the solutions are z=-1 and z=1
The solutions are:
if z=-1, then
sin x=-1   ⇒x= arcsin -1=π+2kπ    (180º+360ºK)   K∈Z
if z=1, then
sin x=1   ⇒ x=arcsin 1=π/2 + 2kπ   (90º+360ºK)   k∈Z
π/2 + 2kπ    U   π+2Kπ=π/2+kπ     k∈Z    ≈(90º+180ºK)
Answer: π/2 + Kπ    or     90º+180ºK          K∈Z
Z=...-3,-2,-1,0,1,2,3,4....