Final answer:
The student's original question about systems a and b lacks complete information but the question is related to linear equations, which are in the form y = mx + b. Practice test content shows examples of linear equations and how to identify independent and dependent variables in real-world scenarios.
Step-by-step explanation:
The student's question relates to systems of linear equations, a topic within the subject of Mathematics. In addressing situations a and b, the given content is incomplete and missing critical information to fully resolve the system of equations. However, to provide assistance with the related practice test content, the primary focus is on understanding what constitutes a linear equation and how to work with them.
Practice Test Analysis
Linear equations are those that can be written in the form y = mx + b, where m and b are constants, representing the slope and y-intercept, respectively. Looking at the practice test options, A, B, and C are indeed linear equations. When sketching these linear equations, the graph will produce a straight line. The provided examples, such as 7 y = 6x + 8, 4y = 8, and y + 7 = 3x, are additional instances of linear equations.
In applications of linear equations, such as the number of flu cases over time or the total cost of attendance, the independent variable is the one that influences or predicts the dependent variable. Correctly identifying the independent variable is crucial in constructing the equation.