Answer:
101
Step-by-step explanation:
According to the Law of Cosines, for any △ABC with side lengths a, b, and c, a2=b2+c2−2bccosA; b2=a2+c2−2accosB; and c2=a2+b2−2abcosC
.
The Law of Cosines can be used because all three side lentghs are known.
Set up the equation for the Law of Cosines:
a2=b2+c2−2bccosA
Substitute the known values into the Law of Cosines:
312=222+182−2(22)(18)cosA
Square the values and multiply:
961=484+324−792cosA
Add:
961=808−792cosA
Subtract 808
from both sides:
153=−792cosA
Divide both sides by −792
:
153−792=cosA
According to this equation m∠A
is equal to the inverse cosine function of −153792
. Write this:
m∠A=cos−1(−153792)
Calculate the value of the inverse cosine −153792
on a calculator:
m∠A≈101°
Therefore, m∠A≈101°
.
C = 2pi(r). Find the radius of the circle first. Then multiply that by 2pi.
Pi=3.14159... 2pi = 2 x 3.14159...
Therefore C = 2 x 3.14159... x r
Answer:
13%
Step-by-step explanation:
not for sure but i think
Answer:
40
Step-by-step explanation:
cause 40+320=360
or subtract 360-320=40
brainliest?
0.15 as a fraction would be 3 over 20 or 3/20. Hope this helps! Plz mark me as brainliest!!! :)
