Question

What’s the names of the shapes x

Answer 1

a - Triangle (equilateral triangle)

b - Paralelogram

c - Square

d - Arrowhead

There is not much to explain here:

A parallelogram is a shape that isn't a square nor a rectangle but it has 2 pairs of parallel sides. Which are represented by the symbols ' and ' or " and ". Where a side named " is parallel to the other side named " and the side name ' is parallel to the other side named '.

An equilateral triangle is a triangle that has a 90º angle. In your case, the 90º angle is the one on the bottom left, represented by the symbol ∟.

Hope it helped,

BioTeacher101