Let us assume that the variables:
d = distance
t = time (in seconds)
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The question assumes that the horse will move 15 meters every second. Therefore:
d = 15t
IF:
t (time) = 1 seconds, then:
d = 15(1)
d = 15
IF:
t (time) = 2 seconds, then:
d = 15(2)
d = 30
IF:
t (time) = 5 seconds, then:
d = 15(5)
d = 75
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As you can see, the graphed numbers are much more larger than the numbers that you have already written, and so it is best to change the numbers. Generally the y-axis is used for time (in this case, seconds), whlie the x-axis is used for distance (in this case, meters).
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