The ratio of the circumference to the diameter is defined as pi
pi=circumference/diameter
that is how they got pi
in this question it woul be 15.7/5 which would be 3.14,
c=2pir
a=pir^2
c=2pir=16pi
divide both sides by 2pi
r=8
a=pir^2
a=pi8^2
a=pi64
a=64pi in²
Answer:
BC < CE < BE < ED < BD
Step-by-step explanation:
In the triangle BCE,
m∠BEC + m∠BCE + m∠CBE = 180°
m∠BEC + 81° + 54° = 180°
m∠BEC = 180 - 135
m∠BEC = 45°
Order of the angles from least to greatest,
m∠BEC < m∠CBE > mBCE
Sides opposite to these sides will be in the same ratio,
BC < CE < BE ----------(1)
Now in ΔBED,
m∠BEC + m∠BED = 180°
m∠BED = 180 - 45
= 135°
Now, m∠BDE + m∠BED + DBE = 180°
11° + 135°+ m∠DBE = 180°
m∠DBE = 180 - 146
= 34°
Order of the angles from least to greatest will be,
∠BDE < ∠DBE < ∠BED
Sides opposite to these angles will be in the same order.
BE < ED < BD ----------(2)
From relation (1) and (2),
BC < CE < BE < ED < BD
The answer to the problem is A
Answer:

Step-by-step explanation:
Given the equation of the circle: 
We wish to express it in a Standard form:
We begin by re-arranging:

Next, divide the coefficient of x by 2, square it and add it to both sides.
Do the same for y.

Next, we factorize

This is the standard form.