Geometry 5

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Geometry 5

by phoenix9801 » Fri Jun 01, 2012 7:15 pm
Questions 1

It Asks what is the value a and b?

Image



Question 2:

It asks what is one-half the area of the circle with center Q? What is The Shaded Region?

Image
Source: — Problem Solving |

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by aneesh.kg » Fri Jun 01, 2012 7:59 pm
Solution 1:

Since it is an isosceles triangle,
a + 5 = b + 7
a = b + 2
without any more data, 'a' and 'b' can have infinite number of values.

Solution 2:

Image

Area of shaded region: [spoiler](2/3)(pi)(r^2)[/spoiler]
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by J N » Wed Mar 20, 2013 3:14 pm
overlap area is broken down into 2 equilateral triangles and 4 lobes

The 120/360 * area will only give area of triangles and 2 lobes, no???


When calculating area of overlap don't you have to figure out area of equilateral triangle and subtract it from 1/6 A to get the area of the small lobe.

shaded area = area of circle - ( 2 small lobes + 120/360*a)