Linear Transformations
Matrix - Vector multiplication as a Linear Transformations
Basis cover the entire plane *
* To get the matrix from original and transformed vectors, we only need information for two vectors [0,1] and [1,0] (see the image below) * 
Matrix Multiplication
We can see matrix product as multiplying two matrix and also as combining two linear transformations into a third linear transformation

Matrix multiplication as combining linear transformations 
Matrices flipped
Indentiy Matrix
- It is the matrix when multiplied by any other matrix will give the same matrix
- Linear transformation by an Identity Matrix will leave the plane intact

Matrix Inverse
The product of a matrix and its Inverse should be an Identity matrix
Inverse Matrix reverses the linear transformation of a matrix

Matrix Inverse 
Finding Matrix Inverse Non-singular matrices will have inverse and singular matrix will not have inverse

Matrix with determinant zero will not have inverse