Answer:
Louise used 5.4 pints of white paint to paint her bedroom wall.
Explanation:
Given:
Total amount of paint used = 7.2 pints
Amount of Blue paint =

We need to find the how many pints of white paint did she use to paint her bedroom walls.
Solution:
Amount in pints of Blue paint =

Now we can say that;
Amount in pints of white paint is equal to Total amount of paint used minus Amount in pints of Blue paint.
framing in equation form we get;
Amount in pints of white paint =

Hence Louise used 5.4 pints of white paint to paint her bedroom wall.