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Answer: 6 inches</h3>
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Explanation:
x = amount (in inches) the spring is stretched
y = force applied (in pounds)
y = kx for some constant k, since x and y vary directly
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Plug in the given info that x = 5 and y = 150 pair up together
Solve for k
150 = k*5
150/5 = k
k = 30
The equation goes from y = kx to y = 30x. Whatever the stretching distance (x) is, you multiply by 30 to get the force needed (y) to pull the spring.
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Plug in y = 180 to solve for x
y = 30x
180 = 30x
30x = 180
x = 180/30
x = 6
The spring will be stretched 6 inches if you apply a force of 180 pounds.
It is linear through a:
Table: the y values have a constant rate of change. For example the y values would be 7, 14, 21, 28 going up by 7 each time. This would not be an example: 6, 12, 17, 18.
Graph: The line of the graph is straight!
Equation: It is in y=mx+b or slope intercept form. Hope this helps!
Answer:
64 km/hr
Step-by-step explanation:
216 - 56 = 160 km on good road
216km / 48 km/hr = 4.5 hours total time
56 km / 28 km/hr = 2 hours on bad road
then 2.5 hours on good road ( for total 4.5 hrs)
160 km / 2.5 hr = 64 km/hr on the good road portion