Final answer:
To model the song downloading situation with a budget of $30, we use the equations 0.79x <= 30 for Company A and 0.99x <= 30 for Company B, where x is the number of songs.
Step-by-step explanation:
To model the situation where a student has $30 to spend on downloading songs, we can write two separate linear equations, one for each company. For Company A, which charges $0.79 per song, the equation will be:
0.79x ≤ 30
Where x represents the number of songs the student can download from Company A. For Company B, which charges $0.99 per song, the equation will be:
0.99x ≤ 30
Again, x represents the number of songs the student can download from Company B, but the cost per song is different, hence a different equation.
These equations are used to determine the maximum number of songs the student can download from each company without exceeding the $30 budget.