Browse · MathNet
PrintIreland
Ireland geometry
Problem
is a rectangle. is a point on between and , and is a point on between and . The area of the triangle is , the area of the triangle is and the area of the triangle is . Find the area of the triangle .

Solution
First Solution: Let and , then ,
Multiply across by and rearrange to get the equation which has only one positive solution . If denotes the area of triangle , the area of is and so .
Second Solution: (after Adam Kielthy) Let and denote the triangle areas as follows from which we obtain , , .
The area of the rectangle is equal to which implies . On the other hand, from , we obtain . Therefore, , i.e. . This implies , hence .
Multiply across by and rearrange to get the equation which has only one positive solution . If denotes the area of triangle , the area of is and so .
Second Solution: (after Adam Kielthy) Let and denote the triangle areas as follows from which we obtain , , .
The area of the rectangle is equal to which implies . On the other hand, from , we obtain . Therefore, , i.e. . This implies , hence .
Final answer
38
Techniques
Distance chasingSimple Equations