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pls help (1 Viewer)
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i. Newport is the vertex. t=-b/2a (vertex formula) = 6/6 =1 hour
ii. Be careful with this one. Total distance is not distance from t=0 to when he gets home.
At the beginning at t=0, x=30
At Newport (t=1) x=33
At home, x=0
Firstly, he travelled 3 kilometers to get to Newport, and then another 33 to get home. So in total he travelled 36km
ii. Be careful with this one. Total distance is not distance from t=0 to when he gets home.
At the beginning at t=0, x=30
At Newport (t=1) x=33
At home, x=0
Firstly, he travelled 3 kilometers to get to Newport, and then another 33 to get home. So in total he travelled 36km
ohhh i get it thank youi. Newport is the vertex. t=-b/2a (vertex formula) = 6/6 =1 hour
ii. Be careful with this one. Total distance is not distance from t=0 to when he gets home.
At the beginning at t=0, x=30
At Newport (t=1) x=33
At home, x=0
Firstly, he travelled 3 kilometers to get to Newport, and then another 33 to get home. So in total he travelled 36km
The problem is, according to the question, he started at Lane Cove and drove to Newport. In driving this trip, his distance from home increased by only 3 km. This is difficult to do when the distance between these suburbs is nearly 30 km...i. Newport is the vertex. t=-b/2a (vertex formula) = 6/6 =1 hour
ii. Be careful with this one. Total distance is not distance from t=0 to when he gets home.
At the beginning at t=0, x=30
At Newport (t=1) x=33
At home, x=0
Firstly, he travelled 3 kilometers to get to Newport, and then another 33 to get home. So in total he travelled 36km
The bigger issue is that this sort of problem usually involves motion in one dimension, so you can work out distance travelled by looking at stopping points. This is (ignoring altitude) motion in two dimensions where we are being told only about the distance from a fixed point. If I travel on a perfect arc 30 km in radius measured from the Opera House (say), then plotting distance against time, I appear to be stationary.
Here, the traveler starts from Lane Cove, 30 km from home, travels 30 km to Newport in one hour, but in so doing increases their distance from home by only 3 km. Without knowing this, one can only conclude that a distance of 3 km was travelled in 1 h, which is slow driving even by the standards of Sydney traffic. Further, the data given does not allow the distance travelled to be determined, though it would limit the positions of "home" to a few possible locations.
The answer sought is the one given above.
The actual answer cannot be found from the data given, and I am not certain is possible even knowing the locations of Lane Cove, Newport, and home. After all, the trip from Newport to home could be a spiral path travelled at great speed so that the distance from home decreases following the graph given. It is a trip of 33 km in displacement, but of unknowable length in distance.
Here, the traveler starts from Lane Cove, 30 km from home, travels 30 km to Newport in one hour, but in so doing increases their distance from home by only 3 km. Without knowing this, one can only conclude that a distance of 3 km was travelled in 1 h, which is slow driving even by the standards of Sydney traffic. Further, the data given does not allow the distance travelled to be determined, though it would limit the positions of "home" to a few possible locations.
The answer sought is the one given above.
The actual answer cannot be found from the data given, and I am not certain is possible even knowing the locations of Lane Cove, Newport, and home. After all, the trip from Newport to home could be a spiral path travelled at great speed so that the distance from home decreases following the graph given. It is a trip of 33 km in displacement, but of unknowable length in distance.