sharon wants to split a collection of erasers into groups of 3.sharon has 63 erasers. how many groups will be created

Drag and drop formal proof. Prove the Polygon Exterior Angle Sum Theorem for the enclosed triangle, that is ∠1+∠2+∠3=360°

jasenka [17]

Answer:

The sum of all the external angles of a triangle is 360°.

Step-by-step explanation:

Let there are n sides in a polygon.

So, there are n internal angles in the polygon, let ∠i1, ∠i2, ∠i3, ..., ∠in are the measure of n internal angles of the polygon.

The measure of external angle corresponding to ∠i1, ∠1= 180°-∠i1,

The measure of external angle corresponding to ∠i2, ∠2 = 180°-∠i2,

Similarly, the measure of external angle corresponding to ∠in, ∠n = 180°-∠in.

Now, the sum of all the external angles of the polygon,

(∠1+∠2+...+∠n)=(180°-∠i1)+(180°-∠i2)+...+(180°-∠in)

=(180°+180°+...n times)-(∠i1+∠i2+...+∠in)

=n x 180° - (∠i1+∠i2+...+∠in)

As ∠i1+∠i2+...+∠in is the sum of all the internal angles of the polygon.

So, the sum of all the external angles of the polygon =

(n x 180°) - (sum of all the internal angles of the polygon).

In the case of a triangle, n=3 and the sum of all the three internal angles, ∠i1+∠i2+∠i3 = 180°.

Therefore, the sum of all the external angles of a triangle,

∠1+∠2+∠3 =3x180°-(∠i1+∠i2+∠i3)

=540°=180°

=360°.

Hence, the sum of all the external angles of a triangle is 360°.

5 0

3 years ago

Write and solve an equation to find the unknown angle.

Julli [10]

There's many properties you can use to find an unknown angle.

There are too many to lists but one core example would be an isosceles triangle that has two adjacent sides and angles.

Let's say that the sides of an isosceles triangle are any number "x"

now since two sides of the triangle are the same we can add these two x's together.

x+x = 2x

now the other side of the triangle can be anything you like. We can call it 4x for this example.

now if we add them all together we'll get 4x+2x=6x

Now since the angles of a triangle add up to 180 degrees
we can equate 6x=180 leaving x to be 30.

Now since x belongs to both sides of the triangle we can say that both angles are congruent as well because the two sides of the triangle are congruent. This is a known triangle law.

Since both angles are now 30 degrees this will leave us with 2(30) = 60

now if we subtract 180 - 60 we'll get 120 which is the remainder of the 3rd angle of the side that corresponds with 4x.
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5 0

3 years ago

Find the measures of an interior angle and an exterior angle of a regular 16-gon

Anastasy [175]

Answer:

2520°

Step-by-step explanation:

The sum of the angles in any triangle is 180°

shape. sides. triangles. sum int angles.

triangle. 180×1=180°

quad. 180×2=360°

pentagon. 180×3=540°

n-sides. n( n−2) 180(n−2)

16-sides. 180×14=2520°

7 0

3 years ago

PLZ HELP, AND PLZ EXPLAIN

shutvik [7]

Answer:

C

Step-by-step explanation:

To make it easy let's start by organizing our information :

AC=12 AND BD=8
ABCD is a rhombus
K and L are the midpoints of sides AD and CD
we notice that the rhombus ABCD is divided into four right triangles

What do you think of when you hear a right triangle ?

The pythagorian theorem !

AC and BD are khown so let's focus on them .

If we concentrated we can notice that AB and BD are cossing each other in the midpoints . why ?

Simply because they are the diagonals of a rhombus .

ow let's apply the pythagorian theorem :

(AC/2)² + (BD/2)² = BC²
6²+4²=52
BC²= 52⇒ $\sqrt{52}$ =BC

Now we khow that : AB=BC=CD=AD= $\sqrt{52}$

This isn't enough . Let's try to figure out a way to calculate the length of KL wich is the base of the triangle

KL is parallel to AC
k is the midpoint of AD and L of DC

I smell something . yes! Thales theorem

KL/AC=DL/DC=DK/AD WE4LL TAKE OLY ONE

KL/12= $\sqrt{52}$ /2* $\sqrt{52}$
KL/12=1/2⇒ KL=6

Now we have the length of the base kl

Now the big boss the height :

notice that you khow the length of KL
BD crosses kl from its midpoint and DL = $\sqrt{52}$ /2

What I want to do is to apply the pythgorian thaorem to khow the lenght of that small part that is not a part of the height of the triangle . I will call it D

DL²=(KL/2)²+D²
52/4= 9+ D²
D² = 52/4-9 +4 SO D=2

now the height of the trigle is H= BD-D= 8-2=6

NOw the area of the triangle is :

A=(KL*H)/2 ⇒ A= (6*6)/2=18

THE ANSWER IS 18 SQ.UN

5 0

3 years ago

If f(x)= 1/x and g(x) = 3x+2 find (g • g)(-4)

OleMash [197]

Answer:

-4g2

Step-by-step explanation:

5 0

3 years ago