Answer:
11.8cm²
Step-by-step explanation:
The area of the regular pentagon is expressed as;
A = pa/2
p is the perimeter of the pentagon
a is the apothem
Since p = 5s
s is the side length, hence;
A = 5sa/2
Get the side length s;
central angle = 360/5
central angle = 72degrees
angle in the right angle triangle =72/2 = 36degrees
Using SOH CAH TOA
sin 36 = x/2
x = 2sin36
x = 1.1755
s = 2x
s = 2.35cm
Get the area
A = 5(2.35)(2)/2
A = 5(2.35)
A = 11.8cm²
Hence the area of the regular pentagon is 11.8cm²
Answer:
------------?
Step-by-step explanation:
The picture in the attached figure
we know that
In similar triangles. The ratio of the lengths of the sides CS and CB must be equal to the ratio of the lengths of sides CR and CA. CS / CB = CR / CA
which can also be written as,
CS / (CS + SB) = CR / (CR + RA)
CS*(CR+RA)=CR*(CS+RA)
CS=2x+1
SB=6x
CR=7.5
RA=18
(2x+1)*[7.5+18]=7.5*[2x+1+18]
(2x+1)*[25.5]=7.5*[2x+19]
(51x+25.5)=15x+142.5
51x-15x=142.5-25.5
36x=117
x=117/36
x=3.25
the answer is x=3.25
31
Step-by-step explanation:
We need to find the value of angle D so that we can solve for X. To do that we need to find the value of angle A and that value will be the same value as D because these angles are the same.
To do that we have to add angles C and B together and that equals 118°. Then we have to realize that all the angles of a triangle add up to 180°. So then we have to subtract 118° from 180° and that equals 62°. So now we have the value of A.
If the value of angle A is 62° then that must be the value of angle D because these two angles are the same. So now that we have the value of angle D we need to solve for X. This equation is asking what times 2 equals the value of X. We know the value of X is 62°. So what times 2 equals 62°?
31×2=62°
Therefore the value of X is 31
Hope this helps! If you have any more questions or you need further clarification please comment down below or message me! Good luck!
Answer: It's either 278 or 178
Step-by-step explanation: I didn't know what equation the question wants you to use so for the first equation it showed I did (10^2+24+10+144) and got 278. For the second equation I did 24+10+144 and got 178. Considering it gave you ax+b as an area equation I just added them (same with the other equation). I don't know whether those are correct of not though.