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Help on question b ASAP

Help on question b ASAP-example-1
User GHB
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1 Answer

2 votes

Answer:

A) a = 108°

B) b = 24°

Explanation:

A) The formula used to calculate the interior angle of any polygon is;

θ = 180(n - 2)/n

where;

n is the number of sides that the regular polygon has

θ is the interior angle

This polygon with angle a has 5 sides.

Thus;

a = 180(5 - 2)/5

a = 108°

B) Looking at the image again, we have 2 equilateral triangles and 1 isosceles triangle.

So the point of the ap ex of the unshaded triangle, the angle at that point is 360°

All angles in an equilateral triangle is 60°. Thus, ap ex angle of isosceles triangle is;

360 - (108 + 60 + 60)

360 - 228 = 132°

Now, the other two angles of the unshaded isosceles triangle are equal.

Thus;

2b + 132 = 180 (sum of angles in a triangle)

2b = 180 - 132

2b = 48

b = 48/2

b = 24°

User Mareq
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3.2k points