Now, let's look at some other problem situations that can be modeled with a linear system of equations.

Example: Brad and his brother Andy have 40 video games between them. Brad has five less than twice as many games as Andy. Formulate a system of equations that could be used to determine the number of video games that each brother has.

Solution:

Let b = the number of video games that Brad has
Let a = the number of video games that Andy has

If Brad has five less than twice as many as Andy, then b = 2a – 5.
If they have 40 games between them, then b + a = 40.

Consequently, the system modeling this situation is:

b + a = 40

b = 2a - 5

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