Answer:
4pi
Step-by-step explanation:
because the formula is A=r^2xpi
9514 1404 393
Answer:
Step-by-step explanation:
With a single application of the Law of Cosines, you can only find one of an unknown side or an unknown angle. The other three elements in the 4-variable equation must be specified.
However, a single application of the LoC can be used to find DE. Then, knowing the three sides, either of the unknown angles can be found from an additional application of the LoC.
So, the answer is "it depends." It is yes to all if finding DE first is allowed. It is "no" to the angles if they must be found without finding DE first.
Since the triangle is an equilateral triangle we know all of it's sides must be the same length, with that in mind the angles that make up the triangle must be equal as well. Knowing that a triangle's three interior angles make up 180 degrees we know that the size of each angle must be one third of this (as each angle must be equal).
180/3 = 60
then we may split the triangle along it's altitude into two special right triangles
more specifically two 30-60-90 triangles.
this means that the side with 30 degrees will be some value "x" where the side for 60 degrees will be related as it is "x*sqrt(3)" and the hypotenuse (which would be the side of the triangle) would be proportionally "2x"
this would mean that the altitude is the side associated with the 60 degree angle as such we can solve for "x" using this.
12= x*sqrt(3)
12/sqrt(3)=x
4sqrt(3)=x (simplifying the radical we get "x" equals 4 square root 3)
now we may solve for the side length of the triangle which is "2x"
2*4sqrt(3) -> 8sqrt (3)
eight square root of three is the answer.
Answer:
yes
Step-by-step explanation:
Answer:
37.68 cm
Step-by-step explanation:
The formula for circumference is C= 2* (3.14) r
First you can actually cut 12 by 1/2
12 * 1/2 is 6. This works because 12 is an even number.
2 * 3.14 (6) gives you 37.68 cm.
So i believe the answer is 37.68 cm.