1.
So for the first question, we know that from home, Nina rides 800 meters (200 + 600). She also rides at a constant speed (straight line). We can assume that as time increases, her distance from school decreases (she’s getting closer to school as she rides her bike). That’s why the slope is negative.
2.
Ok, initially, Nina is 200 meters away from the library (when she is at home.) When she gets to the library, she is now 0 meters away (because she’s AT the library). And we know that the distance between the library and the school is 600 meters, so the distance goes up (because she’s riding away from the library).
Try searching this question up and you’ll be surprised by the results. This question was VERY hard.
