Answer:
Area of the circle = 
Step-by-step explanation:
Circumference = 
Circumference of the circle = 
As,
Area of a circle = 
I can’t understand why everyone complicates this question. It can be easily solved by similar triangles.
In this png, we have something to make sure.
∠B=∠DAB
∠
B
=
∠
D
A
B
(Yes, dab)
This also means AD=BD
A
D
=
B
D
.
This is our basic construction of D, which is going to help us.
∠ADC=∠DAB+∠B=2∠B=∠CAB
∠
A
D
C
=
∠
D
A
B
+
∠
B
=
2
∠
B
=
∠
C
A
B
∠CAD=∠CAB−∠DAB=∠B
∠
C
A
D
=
∠
C
A
B
−
∠
D
A
B
=
∠
B
These are based on the fact that ∠A=2×∠B
∠
A
=
2
×
∠
B
Actually these conditions suffice. Because I am just proving that △ACD∼△BCA
△
A
C
D
∼
△
B
C
A
Similarity makes us realize the following:
ACBC=ADAB
A
C
B
C
=
A
D
A
B
and
ACBC=CDAC
A
C
B
C
=
C
D
A
C
So
AC×AB=BC×AD
A
C
×
A
B
=
B
C
×
A
D
and
AC2=BC×CD
A
C
2
=
B
C
×
C
D
So
BC2=BC×(BD+CD)=BC×(AD+CD)
B
C
2
=
B
C
×
(
B
D
+
C
D
)
=
B
C
×
(
A
D
+
C
D
)
=AC×AB+AC2
=
A
C
×
A
B
+
A
C
2
Q.E.D.
2.4k Views ·
Step-by-step explanation:
v=4/3*π*r^3
v=4/3*22/7*(1/2)^3
v=4/3*22/7*1/8
v=11/21
v=0.52 units^3
Answer:
752
Step-by-step explanation:
IN these type of questions we put the numbers in descending order
Answer:
z = 110°
Step-by-step explanation:
Angles z and the one marked 70° form an linear pair, hence are supplementary.
z = 180° -70° = 110°
<h3>Angles where chords cross</h3>
The angle made by two chords is half the sum of the arcs intercepted by those chords. Here, that means ...
70° = 1/2(60° +x) ⇒ x = 140° -60° = 80°
The arc w completes the circle of 360°, so we have ...
w +x +79° +60° = 360° ⇒ w = 360° -219° = 141°
Finally, z is the average of w and 79°:
z = (w +79°)/2 = (141° +79°)/2 = 110° . . . as above
