Using cosine law.
b= sqrt(38^2 + 18^2 - 2(38)(18) Cos 36)
using calculator solve.
b = sqrt (1444 + 324 - 1106.75)
b = 25.75
Answer:
We have a small circle, that is dilated by a factor of 5/3 creating a larger circle.
If the smaller circle has a diameter D, then after the dilation, the larger circle will have a diameter equal to: (5/3)*D
We know that the area of the larger circle is:
A = 100*pi cm^2.
And the area of a circle of diameter d, is:
a = pi*(d/2)^2
knowing that the diameter of the large circle is (5/3)*D, we can find the value of D.
A = pi*( (5/3)*D/2)^2 = 100*pi cm^2
let's solve this for D:
pi*( (5/3)*D/2)^2 = 100*pi cm^2
( (5/3)*D/2)^2 = 100 cm^2
( (5/3)*D/2) = √(100 cm^2) = 10cm
D/2 = (3/5)*10cm
D = 2*(3/5)*10cm = 12cm.
Then the area of the smaller circle will be:
a = pi*(D/2)^2 = pi*(12cm/2)^2 = pi*(6cm)^2 = pi*36 cm^2
and pi = 3.14
a = pi*36 cm^2 = 3.14*36cm^2 = 113.04 cm^2
Answer: 127
Step-by-step explanation:
angle b is 127 as well because they're vertical angles and vertical angles are equal to each other.
One could use the relation
where
are two vectors,
denotes the norm of that vector, and
is the angle between the two vectors.
Then the two vectors will be parallel if
or
.
