Linear Algebra- Finding a Coordinate Matrix Example

These are my lecture for University and College level students.
The coordinate matrix of x in R2 relative to the (nonstandard) ordered basis
B = {v1, v2} = {(1, 0), (1, 2)} is
[x]B = [3 2].
Find the coordinate matrix of x relative to the standard basis
B′ = {u1, u2} = {(1, 0), (0, 1)}.