Question

angles which have a common arm and whose other arms form a straight line are said to be ________ angle​

Answer 1

Angles which have a common arm and whose other arms form a straight line are said to be Alternate angle​.

Explanation:

since, we know that-

Alternate angle :- when two angles are formed on opposite sides of a line that crosses two other lines. Also, they have common arm and others arm are forming a straight line.

here, it is given that - angles which have a common arm and whose other arms form a straight line.

so, according to definition of alternate angles.

above given is an alternate angle.    

Hence, Angles which have a common arm and whose other arms form a straight line are said to be Alternate angle​.