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This shape has two equal angles. Work out the value of x. I need to refresh this. I have forgotten how. ​

This shape has two equal angles. Work out the value of x. I need to refresh this. I-example-1
User Bsberry
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2 Answers

2 votes
360-110 = 250

2x = 360-250-50
2x = 60
x = 60/2
x = 30
User Dhaumann
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2.8k points
6 votes

Answer:

x = 30°

Explanation:

A polygon is a 2D shape with at least three sides.

Polygons can be regular or irregular. If the angles are all equal, and all the sides are equal length, it is a regular polygon.

Therefore, this shape is an irregular polygon with 4 sides and 4 interior angles.

The formula for calculating the sum of the interior angles of any polygon is: (n - 2) x 180° (where n is the number of sides)

Therefore, for our polygon, the sum of the interior angles is:

(4 - 2) x 180 = 360°

The four angles of this polygon are 50°, x°, x° and the reflex angle (this is the interior angle the "other side" of the 110° angle).

We know that the sum of angles around a point is 360°

Therefore, the reflex angle = 360 - 110 = 250°

So now we can create an equation where we sum all the interior angles and equal them to 360°, then solve for x:

⇒ 50 + x + x + 250 = 360

⇒ 50 + 2x + 250 = 360

⇒ 2x = 360 - 250 - 50

⇒ 2x = 60

⇒ x = 60 ÷ 2

⇒ x = 30°

Reflex angle = an angle greater than 180° and less than 360°

User Eoin Campbell
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