The perimeter of a quadrilateral is . If the first three sides of a quadrilateral, taken in order are , and respectively, and the angle between fourth side and the third side is a right angle, find the area of the quadrilateral.
Answer:
Area:
- The following picture shows the quadrilateral ,
The perimeter of the quadrilateral
- Let's draw a line .
The is the right angled triangle.
- Now, we can see that, this quadrilateral consists of the triangles and .
The area of the can be calculated using Heron's formula since all sides of the triangle are known.
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