SAT Question 74c03c21: Systems of Linear Equations answer and explanation with Desmos solution

Choice B is correct. If the bus traveled at an average speed of $55$ miles per hour (mph) on the highway for $x$ hours, then the bus traveled $55x$ miles on the highway. If the bus traveled at an average speed of $25$ mph on local roads for $y$ hours, then the bus traveled $25y$ miles on local roads. It's given that the trip was $160$ miles. This can be represented by the equation $55x+25y=160$. It's also given that the trip took $4$ hours. This can be represented by the equation $x+y=4$. Therefore, the system consisting of the equations $55x+25y=160$ and $x+y=4$ represents this situation.