X is equal to 30 (vertically opposite angles)

y=180-50
=130 degrees (angles in a straight line equal to 180)

z=180-130-30 (angle sum of a triangle equal to 180)
z=20 degrees

6 0

2 years ago

What percentage of the semi circle is shaded? <br>

mezya [45]

The percentage of the semicircle shaded section is approximately 23,606 %.

The percentage of the area of the semicircle is equal to the ratio of the semicircle area minus the half-cross area to the semicircle area. In other words, we have the following expression:

$r = \left(\frac{A_{s}-A_{h}}{A_{s}} \right)\times 100\,\%$

$r = \left(1-\frac{A_{h}}{A_{s}} \right)\times 100\,\%$ (1)

Where:

$A_{h}$ - Area of the half cross, in square centimeters.
$A_{s}$ - Area of the semicircle, in square centimeters.
$r$ - Percentage of the shaded section of the semicircle.

And the percentage of the shaded section is:

$r = \left[1-\frac{4 \cdot (2\,cm)^{2}+4\cdot \left(\frac{1}{2} \right)\cdot (2\,cm)^{2}}{0.5\cdot \pi\cdot (16\,cm^{2}+4\,cm^{2})} \right]\times 100$

$r \approx 23.606\,\%$

The percentage of the semicircle shaded section is approximately 23,606 %.

We kindly invite to check this question on percentages: brainly.com/question/15469506

3 0

2 years ago

-5+(63/9)<br> Can someone help me please.

Margarita [4]

Answer:

Step-by-step explanation:

3 0

3 years ago

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