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2 years ago

Lines l and k are parallel to each other. A=120 degrees. and C=80 degrees. What is the number of degrees in B??

Mathematics

1 answer:

Aleonysh [2.5K]2 years ago

5 0

Answer:

B = 160°

Step-by-step explanation:

This is how I solved it (I hope the explanation isn't too confusing):

Since L and K are parallel, I drew a straight line from A to B. By doing this, I'm making a triangle: ΔABC

Then I solved for the angles of the triangle. First, we are given that ∠C = 80° and ∠A = 120°. Although, when I drew the vertical line from A to B, it made a 90° (see attachment).

So what we basically did was break ∠A into two parts: an angle inside ΔABC and one outside. To find the interior angle, simply subtract 90° from 120° to get 30°.

There are 180° in a triangle, so add the two interior angles you know:

30° + 80° = 110°

Then subtract 110° from 180° to find the final interior angle which is:

180° - 110° = 70°.

To find the measure of angle B, you must add all of the parts together, so the 90° outside angle and the 70° interior angle:

90° + 70° = 160°

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fgiga [73]

Answer:

A= 75.06 Sq Cm

Step-by-step explanation:

Please refer to the picture attached with this.

In ΔABD

AB = 8.5 , AD = 6 and say BD = x

Applying Pythagoras theorem in this triangle

Pythagoras theorem says

$a^2+b^2=c^{2}$

where c is the side opposite to the right angle, and b and a are the other two sides of the right angled triangle.

$x^2+6^2=8.5^{2}$

$x^2=72.25-36$

$x^2=36.25$

$x=6.02$

Hence side $a = x +19$

a = 6.02+19

a = 25.02

Now we apply the formula for area of a triangle which is given as

$A=\frac{1}{2}\times b \times h$

Where b is the base , here we have base as a = 25.02

h is the height , here h = 6

Putting these values in Formula we get

$A=\frac{1}{2}\times 25.02 \times 6$

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$A=75.06$

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5 0

3 years ago

If angle∠ A and angle∠ B are supplementary angles and angle∠ A is eighteight times as large as angle∠ B, find the measures of a

Shalnov [3]

A = 8B
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4 0

3 years ago

Help fill in the blanks no

DerKrebs [107]

Answer:

Here is the full proof:

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DC ⊥ AD Given

∠ADC = 90° Definition of perpendicular lines

BC ⊥ AB Given

∠ABC = 90° Definition of perpendicular lines

∠ADC ≅ ∠ABC Right angles are congruent

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7 0

2 years ago

Step by step<br> Please urgent

kotegsom [21]

Answer:

Below in bold.

Step-by-step explanation:

1) ( a^2 + b^2 = (a + b)^2 - 2ab

= 29 - 2(6)

= 29-12

= 17.

2). (x - y)^2 = x^2 + y^2 - 2xy

so 20 = 18 - 2xy

2xy = 18-20 = -2

xy = -1.

3). 1/x + x = 7

(1/ x + x)^2 = 1/x^2 + x^2 +x/x + x/x

= 1/x^2 + x^2 + 2

But(1/x + x)^2 = 7^2 = 49

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6 0

3 years ago

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11Alexandr11 [23.1K]

Answer:

Step-by-step explanation:

Given the following

GE = 3x - 11 FD = 2x

Let us assume GE is parallel to FD, hence GE = FD

3x - 11 = 2x

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x = 11

Get GE

GE = 3x - 11

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GE = 22

Hence the length of GE is 22

3 0

2 years ago