Equilateral Triangle: All 3 sides of a Triangle are equal in length
Isosceles Triangle: Two sides of Triangle are equal in length
Scalene: Triangle has different side lengths
So, for example, when you see Q1, you estimate the length of each side and think it is Scalene Triangle because all of its sides are of different length. (You can also use a ruler to find out the side lengths if it can be used for scale)
Q2, you can say that the side lengths AC and BC look similar, so it is an Isosceles Triangle
Q6, when you look at the side lengths, you can tell it is an equilateral Triangle because all the sides are equal in length
You can try the rest and check for yourself. If you still have any doubts, you could ask me. I hope this information helps you.
