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3 years ago

A regular pentagon ABCDE is shown Work out the size of X

Mathematics

2 answers:

nikdorinn [45]3 years ago

7 0

The sum of the angles in a pentagon is 540°.

This means that each angle is 108°.

Inside you pentagon, a triangle is drawn. This triangle is isosceles, because the corners are on the points of the regular pentagon. You know that angle C is 108°.

Angles in a triangle add up to 180°.

B and D will be the same size as this is isosceles.

180°-108° = 72°

This is B and D. You only need one of these, so you divide by 2.

The answer is 36°.

Hope this helps :)

Goshia [24]3 years ago

4 0

Answer:

X = 36°

Step-by-step explanation:

ABCDE regular pentagon => C = 108°

x = A = (180° - 108) : 2 = 72 : 2 = 36 °

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Two angles are complementary. two times the measure of one is equal to 40% of the measure of the other. find the measure of both

Nostrana [21]

The measure of both angles are 112.5 and 68.5 degrees

<h3>Complementary angles</h3>

The sum of two complementary angles is 90 degrees.

If two angles are complementary, then;

x + y = 90

x = 90 - y..........1

where x and y are the angles

If two times the measure of one is equal to 40% of the measure of the other then;

2x = 0.4y ............2

Substitute equation 1 into 2

2(90-y) = 0.4y

180 - 2y = 0.4y

180 = -0.4y + 2y

1.6y = 180

Divide both sides by 1.6

1.6y/1.6 = 180/1.6

y = 112.5 degrees

For the other angle

x= 180 - y

x = 180 -112.5

x = 68.5 degrees

Hence the measure of both angles are 112.5 and 68.5 degrees

Learn more on complementary angles here: brainly.com/question/16281260

#SPJ1

8 0

9 months ago

The vector has components +5 and +7 along the x- and y-axes respectively. along a set of axes rotated 90 degrees counterclockwis

lisabon 2012 [21]

Refer to the diagram shown below.

Let the coordinates of the rotated vector be (a,b).
From the Pythagorean theorem,
d = √(5² + 7²) = 8.6023

The angle θ is given by
tan θ = 7/5 = 1.4
θ = tan⁻¹ 1.4 = 54.46°
φ = 180 - (90 + 54.46) = 35.54°

The coordinates of the rotated vector are
a = - d cos φ = - 8.6023*cos(35.54) = 7
b = d sin φ = 8.6023*sin(35.54) = 5

Answer: (-7, 5)

6 0

3 years ago

Read 2 more answers

Which shape is an equivalent fraction to this fraction? 3/4<br><br> 10/14<br> 7/8<br> 6/8<br> 4/7

Pavlova-9 [17]

Answer:

6/8

Step-by-step explanation:

3/4

Multiply by 2/2

3/4 *2/2 = 6/8

3 0

3 years ago

Write an equation of the line through each pair of points in slope-intercept form.

ASHA 777 [7]

Answer:

see below

Step-by-step explanation:

a) (– 3, –2) and (–3, 4)

First you want to find the slope of the line that passes through these points. To find the slope of the line, we use the slope formula: (y₂ - y₁) / (x₂ - x₁)

Plug in these values:

(4 - (-2) / (-3 - (-3))

Simplify the parentheses.

= (4 + 2) / (-3 + 3)

Simplify the fraction.

(6) / (0)

= undefined

If your slope is undefined, it is a vertical line. The equation of a vertical line is x = #.

In this case, the x-coordinate for both points is -3.

Therefore, your equation is x = -3.

b) (3, 2) and (–4, –5)

First you want to find the slope of the line that passes through these points. To find the slope of the line, we use the slope formula: (y₂ - y₁) / (x₂ - x₁)

Plug in these values:

(-5 - 2) / (-4 - 3)

Simplify the parentheses.

= (-7) / (-7)

Simplify the fraction.

-7/-7

= 1

This is your slope. Plug this value into the standard slope-intercept equation of y = mx + b.

y = 1x + b or y = x + b

To find b, we want to plug in a value that we know is on this line: in this case, I will use the first point (3, 2). Plug in the x and y values into the x and y of the standard equation.

2 = 1(3) + b

To find b, multiply the slope and the input of x(3)

2 = 3 + b

Now, subtract 3 from both sides to isolate b.

-1 = b

Plug this into your standard equation.

y = x - 1

This is your equation.

Check this by plugging in the other point you have not checked yet (-4, -5).

y = 1x - 1

-5 = 1(-4) - 1

-5 = -4 - 1

-5 = -5

Your equation is correct.

Hope this helps!

7 0

3 years ago

PLZ HELP ME PLEASE!!!!... WILL GIVE BRAINLIEST. THANKYOU!

belka [17]

Answer:

1) 0.5

2)-2

3)-23

Step-by-step explanation:

1) -3×1=-3

-3+2.5= 0.5

2) -3×1.5=-4.5

-4.5+2.5= -2

3) -3×8.5=-25.5

-25.5+2.5=-23

6 0

3 years ago