Answer:
The ratio of circumference to diameter is a constant
Step-by-step explanation:
The first line on the page tells you the relation: the ratio of the circumference to the diameter is about 3.14.
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Another way to say this is that the circumference is about 3.14 times the diameter.
Answer:

Step-by-step explanation:

Let's solve the second equation for a to later on replace it in the first equation.

Now plug this into the first equation.

Distribute the 9

Break down the fraction.

Simplify.

Subtract 

Combine like terms.



Muliply by the reciprocal or inverted fraction next to b.


Now plug this value into any of the equations to find the value of a.

Answer:
A. Plane B because it was 9.33 miles away
B. 48 units
Step-by-step explanation:
A. Since the airplanes fly at an angle to the runway, their direction forms a triangle with the runway with their height above the ground as the opposite of the angle and their distance from the airport as the hypotenuse.
So for airplane A with 44° angle of departure,
sin44° = y/h where y = height above the ground and h = distance from airport
So h = y/sin44° = 6/sin44° = 8.64 miles
So for airplane B with 40° angle of departure,
sin40° = y/H where y = height above the ground and H = distance from airport
So H = y/sin40° = 6/sin40° = 9.33 miles
Since airplane B is at 9.33 miles away from the airport whereas airplane A is 8.64 miles from the airport, airplane B is farther away.
B. We know that scale factor = new size/original size
Our scale factor = 4 and original size = 12 units. So,
new size = scale factor original size = 4 × 12 = 48 units.
Answer:
Part 1) 
Part 2) 
Step-by-step explanation:
<u><em>The picture of the question in the attached figure</em></u>
Part 1) Find the area
we know that
The area of the shape is equal to the area of a quarter of circle minus the area of an isosceles right triangle
so

we have that the base and the height of triangle is equal to the radius of the circle

substitute

simplify
Factor 36

Part 2) Find the perimeter
The perimeter of the figure is equal to the circumference of a quarter of circle plus the hypotenuse of the right triangle
The circumference of a quarter of circle is equal to

substitute the given values

Applying the Pythagorean Theorem
The hypotenuse of right triangle is equal to

simplify

Find the perimeter

simplify
Factor 6

Not quite sure what you mean by brackets, but you can get the solution to this equation in a few steps:
<span>(-2x - 1)</span>² <span>= 0 ... square root both sides to eliminate the squared binomial
</span>√(-2x - 1)² = √0 ... simplify; the square is canceled out and the root of 0 brings you back to 0
-2x - 1 = 0 ... solve like a two-step equation
-2x = 1
x = -1/2 is your x-value.