Maths puzzle

3. This lemma is used to find the HCF of two numbers
4. When three points are collinear, the ____ of the triangle is zero
6. A series of number with same _____ difference is an AP.
7. Two triangles with their two corresponding sides and the angle including them are equal are_____
8. in trignometry,the ratio of hypoteneous and perpendicular of the base angle is called _____
9. Basic proportionality theorem is also known as ____ theorem

1. A polynomial of degree 2 is called____ polynomial
2. the angle between the line of sight and the base when object is at some height is called angle of____
5. the region between a chord and an arc of circle is called _____
6. a collection of all the points which are equidistant from a fixed point is called____