View Full Version : Event-related graph (9th grade algebra)
andiesmom1008
Oct 24, 2009, 03:35 PM
I am helping my daughter with her homework, so don't worry about giving me the answer. Lol :) The question is to sketch the graph of the following scenario: Jimmy left his house and rode his bike to the grocery store at a steady pace. He stopped at the store and bought ice cream. He then rode home at a much faster speed. I believe the answer to this forms a triangle, but I need confirmation. Thank you for your help!
Unknown008
Oct 25, 2009, 12:05 AM
I guess it is a distance time graph. Well, strictly speaking will be some sort of triangle, rectangle, trapezium shape.
Speed = Distance/Time and therefore Distance = Speed x Time
So, speed is basically the slope of the graph, putting the equation as Y = mX, the y axis being the distance and the x axis being the time.
A steady speed means a constant gradient.
First, the gradient is steady.
Then, Jimmy stopped, meaning that as time goes on, the distance travelled remains the same.
Later, he returns home. The distance travelled (height of graph) will increase again, but since the speed is higher, the slope is sharper.
andiesmom1008
Oct 25, 2009, 03:20 PM
I should have mentioned... The axes provided are: x axis = time, y axis = distance from home. So, yes, I guess a trapezoid would be more of the shape I was seeing for the answer. I needed confirmation of the line going backward for the second part of the problem, as opposed to forward. Thank you!
Unknown008
Oct 25, 2009, 10:17 PM
Yes, if it is distance, then the graph will not go back. If it was displacement (which is distance between final point and initial point, regardless of the path taken) then the graph will go backwards.
Happy to help :)