Answer:
A = 25√3 cm²
Step-by-step explanation:
View 5√3 cm as being the height of an equilateral triangle whose base is at the bottom of the purple figure. To find the area of one such triangle, we use the area-of-a-triangle formula A = (1/2)(b)(h).
opp
Using the sine function sin Ф = --------
hyp
we find the length of the hypotenuse, which is also the radius of the octagon, and because this is an equilateral triangle, is also the length of the base:
√3 5√3 cm
sin 60° = -------- = ------------- , which produces the value of hyp:
2 hyp
√3 5√3 cm
-------- = ------------- , which produces the value of hyp:
2 hyp
√3·hyp = 10√3, or hyp = 10 cm
Then the area of this one triangle is A = (1/2)(b)(h), or
A = (1/2) (10 cm)(5√3 cm) = 25√3 cm²
If you would like to convert meters to kilometers, you can calculate this using the following step:
1 meter = 0.001 kilometers
1900 m = 1900 * 0.001 km = 1.9 km
If the tunnel is about 1900 m = 1.9 km long, then this is a little less than 2 km, because 1.9 km < 2 km.
Answer:
f(4) = 22
Step-by-step explanation:
I think that you type wrongly.
we have f(1) = -5
and f(n) = f(n-1) + 9
Find f(4)
Then
with n= 2 we have f(2) = f(1) + 9 = - 5+ 9= 4
with n= 3 we have f(3) = f(2) + 9 = 4 + 9= 13
and finally with n= 4 we find f(4) = f(3) + 9 = 13+ 9= 22
So f(4) = 22
Hope you understand.
Answer:
0.104
Step-by-step explanation:
10.40 · 0.01 = 0.104