CBSE Class 9 Answered

Before constructing, look at the given conditions carefully. 

Example: In ΔABC, base BC = 7.5 cm, the difference of the other two sides, AB – AC or AC – AB = 2.5 cm and one base angle is 45°.

If from the given information, you find AB - AC is given then use case 1 only.

 If construction of right triangle is to be done where difference between hypotenuse and one side is given, then you know that hypotenuse is the longest side, so then do accordingly.