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In ADEF, the measure of ZF=90°; the measure of ZD=67°, and FD = 7.4 feet. Find
the length of EF to the nearest tenth of a foot.
E
X
67°
F
D
7.4

Answer:

o         Identify some basic parts of a circle, such as the radius and diameter

o         Calculate the circumference of a circle

o         Calculate the area of a circle

In this article, we will consider a geometric figure that does not involve line segments, but is instead curved: the circle. We will apply what we know about algebra to the study of circles and thereby determine some of the properties of these figures.

Introduction to Circles

Imagine a point P having a specific location; next, imagine all the possible points that are some fixed distance r from point P. A few of these points are illustrated below. If we were to draw all of the (infinite number of) points that are a distance r from P, we would end up with a circle, which is shown below as a solid line.

Thus, a circle is simply the set of all points equidistant (that is, all the same distance) from a center point (P in the example above). The distance r from the center of the circle to the circle itself is called the radius; twice the radius (2r) is called the diameter. The radius and diameter are illustrated below.

The Circumference of a Circle

As with triangles and rectangles, we can attempt to derive formulas for the area and "perimeter" of a circle. Unlike triangles, rectangles, and other such figures, the distance around the outside of the circle is called the circumference rather than the perimeter-the concept, however, is essentially the same. Calculating the circumference of a circle is not as easy as calculating the perimeter of a rectangle or triangle, however. Given an object in real life having the shape of a circle, one approach might be to wrap a string exactly once around the object and then straighten the string and measure its length. Such a process is illustrated below.

Obviously, as we increase the diameter (or radius) of a circle, the circle gets bigger, and hence, the circumference of the circle also gets bigger. We are led to think that there is therefore some relationship between the circumference and the diameter. As it turns out, if we measure the circumference and the diameter of any circle, we always find that the circumference is slightly more than three times the diameter. The two example circles below illustrate this point, where D is the diameter and C the circumference of each circle.

Again, in each case, the circumference is slightly more than three times the diameter of the circle. If we divide the circumference of any circle by its diameter, we end up with a constant number. This constant, which we label with the Greek symbol π (pi), is approximately 3.141593. The exact value of π is unknown, and it is suspected that pi is an irrational number (a non-repeating decimal, which therefore cannot be expressed as a fraction with an integer numerator and integer denominator). Let's write out the relationship mentioned above: the quotient of the circumference (C) divided by the diameter (D) is the constant number π.

We can derive an expression for the circumference in terms of the diameter by multiplying both sides of the expression above by D, thereby isolating C.

Because the diameter is twice the radius (in other words, D = 2r), we can substitute 2r for D in the above expression.

Thus, we can calculate the circumference of a circle if we know the circle's radius (or, consequently, its diameter). For most calculations that require a decimal answer, estimating π as 3.14 is often sufficient. For instance, if a circle has a radius of 3 meters, then its circumference C is the following.

The answer above is exact (even though it is written in terms of the symbol π). If we need an approximate numerical answer, we can estimate π as 3.14. Then,

Interested in learning more? Why not take an online class in Pre-Algebra?

The symbol ≈ simply means "approximately equal to."

Practice Problem: A circle has a radius of 15 inches. What is its circumference?

Solution: Let's start by drawing a diagram of the situation. This approach can be very helpful, especially in situations involving circles, where the radius and diameter can easily be confused.

Step-by-step explanation:

Answer:

56cm

Step-by-step explanation:

The radius is half the diameter so times the radius by two to find the width of the diameter. 28 x 2 = 56cm

Answer:

nljgdetbeybrybdtbrbrtbetbrynrynenehtnehymyrumeymryjmryj ryu

Answer:

Use the slope-intercept form y=mx+b to find the slope m. m=−1

Step-by-step explanation:

lets take the x's away from: -5x+4x

That will be -5+4

-5+4=-1

Because remember:

When adding positive numbers, count to the right.

When adding negative numbers, count to the left.

When subtracting positive numbers, count to the left.

When subtracting negative numbers, count to the right.

I hope this helps.       :)

Answer:

m= 4

Step-by-step explanation:

Rewrite the slope-intercept form

y = 4x - 5

the using the slope-intercept form, the slope-intercept is 4

sorry if this doesn't help

Answer:

14 ft squared

Step-by-step explanation:

Area is length x width so 7 x 2 = 14.

Hope this helps :D

Answer:

The equation for charge is = current x times

Answer:

hope this will help you

Step-by-step explanation:

.........

Answer:

(4th option) 254.34 cm

Step-by-step explanation:

Area of a circle = pi (r)^2

r=radius of circle which is half of diameter.

diameter=12+6=18

So, radius is half of 18 = 9

Plug it into the formula:

[tex]\pi (9)^{2}[/tex]

And you should get 254.34 cm^2

Answer:

Step-by-step explanation:

area of a circle is pi * r^2

r for the big circle is 1/2 of 18 or 9

pi * 9^2 = 254.469

Answer:

1000

Step-by-step explanation:

Answer:

20 × 50

= 1000

Although u say dividend, which is division, not too sure here

Answer:

Slope = Rise over Run

Rise = 2

Run = 3

Slope = 2/3

Let me know  if this helps!

Answer:

i think its 274,182,025 cubic feet

Step-by-step explanation:

.

Answer:

(3, 24)

Step-by-step explanation:

Answer:

f=3

Step-by-step explanation:

The intervals means that angle f is between the quadrant 1.

Using that, we can use this identity

[tex] \sin(x) = \cos(y) [/tex]

where x+y=90

[tex]22f - 1 + 7f + 4 = 90[/tex]

[tex]29f + 3 = 90[/tex]

[tex]29f = 87[/tex]

[tex]f = 3[/tex]

Answer:

La cantidad que Javier paga como impuesto, A es de 1.200 €

La cantidad que Antonio paga como impuesto, B es 900 €

El importe que paga Elvira como impuesto, C es de 1.000 €

Step-by-step explanation:

Dejemos que 'A', 'B' y 'C', representen la cantidad que pagan Javier, Antonio y Elvira respectivamente, y que 'k' represente la constante de proporcionalidad, por proporcionalidad inversa, tenemos;

A = k / 1500, B = k / 2000, C = k / 1800

A + B + C = 3100

∴ k / 1500 + k / 2000 + k / 1800 = 3100

Simplificando la ecuación anterior usando una calculadora gráfica da;

31 · k / 18 000 = 3100

k = 18.000 × 3.100 / 31 = 1.800.000

k = 1.800.000

La cantidad que Javier paga como impuesto, A = 1.800.000 / 1.500 = 1.200

La cantidad que Antonio paga como impuesto, B = 1.800.000 / 2.000 = 900

La cantidad que paga Elvira como impuesto, C = 1.800.000 / 1.800 = 1.000

Answer:

The numbers should be A. 5 and C. 0.

Hope I Helped

Answer:

the answer and only answer is C. 0

Step-by-step explanation:

I took the test and it's just C. 0 and i got 0 because i said A. 5 and C. 0 but it's just C. 0

hoped it helped :D

0.45 or %45 is left of the circular cake.

Hope this helps; have a great day!

Answer:

7x

Step-by-step explanation:

To purchase 7 tickets at the same rate ;

Mathematically, Total Cost of an item is :

Cost = unit price * quantity

Here,

quantity = 7 tickets

Since price per ticket(rate) is the same ; then we can take rate as x

Hence, the cost of the 7 tickets is :

Quantity * rate

7 * x = 7x

Answer:

4

Step-by-step explanation:

3x + 5 > 16

3x > 16 - 5

3x > 11

x > 11 / 3

x > 3.6666...

The smallest value would be 4.

Answer:

4

Step-by-step explanation:

Given

3x + 5 > 16 ( subtract 5 from both sides )

3x > 11 ( divide both sides by 3 )

x > [tex]\frac{11}{3}[/tex] , that is

x > 3 [tex]\frac{2}{3}[/tex]

If x is an integer then the smallest value of x is 4

Answer:

In geometry, the tangent line (or simply tangent) to a plane curve at a given point is the straight line that "just touches" the curve at that point. Leibniz defined it as the line through a pair of infinitely close points on the curve. ... The word "tangent" comes from the Latin tangere, "to touch".

Step-by-step explanation:

A straight line touching a curve at a single point without crossing it there is tangent.

Answer:

√{32×32×4}=√{32²×2²}=±(32×2)=±64

Answer:

64 will be your answer

Step-by-step explanation:

......

Answer:

Hanno moves faster than Simone.

Step-by-step explanation:

Simone: 25x100=2500m or 2.5km in 25x12=300 seconds or 5 minutes

Hanno- 2.5 km in 4minutes

So, Hanno moves 1 minute faster.

Please mark as brainliest.

Answer:

FGJ +JGH=90

25+x. =90

x. =90-25

x. =65°

Answer:

65

Step-by-step explanation:

Hey There!

Those are a pair of complementary angles meaning that they will add up to equal 90

so to find x we subtract the given angle from 90

90-25=65

therefore x=65

Answer:

Then maybe pay attention in class and know what to do and not ask strangers for help. We answer to try and help. Not like we get paid. We literally are just trying to help

Answer:

$180.806

Step-by-step explanation:

The computation of the total amount paid for the trip is shown below;

As we know that

Simple interest = Principal × rate of interest × time period

= (67.70 + 62.34 + 45.50) × 12% × 3 months ÷ 12 months

= 5.2662

Now the amount is

= Principal + simple interest

= 175.54 + 5.2662

= $180.806

Answer:

4(x+ 1.75)

Step-by-step explanation:

Answer: 4

i wish that helped

Answer:

{0, 1, 16, 81}

Step-by-step explanation:

If the domain of this function is the set {0, 1, 4, 9}, we find the set representing the range by evaluating the function at each of the four values in the domain.

f(0) = 0

f(1) = 1

f(4) = 16

f(9) = 81

and so the range is the set {0, 1, 16, 81}.