document.write( "Question 858632: My problem is a bus from London to Penzance leaves London at 13.00 hours and travels at 60km/h.
\n" ); document.write( "A car averaging 80km/h leaves London by the same route an hour later.
\n" ); document.write( "Find graphically when the car overtakes the bus
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Algebra.Com's Answer #517309 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
let x = number of hours
\n" ); document.write( "let y = number of kilometers
\n" ); document.write( "for the bus, y = 60x
\n" ); document.write( "for the car, y = 80(x-1)
\n" ); document.write( "what happens is:
\n" ); document.write( "when x = 0, the bus is at 0 miles traveled.
\n" ); document.write( "when x = 1, the car is at 0 miles traveled.
\n" ); document.write( "disregard any negative values below x-axis or to the left of the y-axis as those are invalid values because the number of hours can't be less than 0 and the number of miles can't be less than 0.
\n" ); document.write( "the only reason they are shown is to show the x-axis values and the y-axis values.
\n" ); document.write( "if the graph is shown starting at 0, you wont' be able to see them.
\n" ); document.write( "the graph below the first graph shows you what i mean.
\n" ); document.write( "it's the same graph but the x-axis starts at 0 and the y-axis starts at 0.
\n" ); document.write( "you can see that, while the second graph is technically more correct since negative values are not allowed, the values on the y-axis and the x-axis don't show up which is why the first graph shows some negative values as well even though they are not valid.
\n" ); document.write( "first graph is shown below:
\n" ); document.write( "\"graph%28600%2C600%2C-1%2C5%2C-100%2C400%2C60x%2C80%28x-1%29%29\"
\n" ); document.write( "second graph is shown below:
\n" ); document.write( "\"graph%28600%2C600%2C0%2C5%2C0%2C400%2C60x%2C80%28x-1%29%29\"
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