Explained why every linear transformation of the plane can be represented by a 2x2 matrix. 

<br><br> Stated that: (i) reflections in a line through the origin of the plane are linear transformation; (ii) rotations about the origin of the plane are linear transformations; (iii) the composite of any two linear transformations of the plane is linear.

<br><br>
Stated a theorem which asserts that compositiExplained why every linear transformation of the plane can be represented by a 2x2 matrix. Stated a theorem that asserts that composition of transformations corresponds to multiplication of matrices. Matrix multiplication has been invented just so that this theorem is true. on of linear transformations corresponds to multiplication of matrices. Matrix multiplication has been invented just so that this theorem is true. 

<br><br>
Derived the matrix of a rotation of the plane about the origin.