Answer:

<em>Sure hope this helps you :D</em>
Answer:
The slope of this line is -2
Step-by-step explanation:
2x - 5y =9
-5y = -2x + 9 (Subtract 2x from each side)
y= -2x + 14 (add 5 to each side)
-2 is the slope
We need to convert the mileage from mi/gal units into to km/L units using the conversion factors.
(31.0 mi/gal) x (1 km / 0.6214 mi) x (1 gal / 3.78 L) = 13.20 km/L
Next, we divide the distance by the mileage.
(142 km) / (13.20 km/L) = 10.79 L
<span>Therefore, you need 10.79 liters of gasoline.</span>
Problem 1
The error is 2 inches since her estimate is 2 inches off the true value.
We can think of it like this
4 feet = 4*12 = 48 inches
4 feet, 2 inches = 4 ft + 2 in = 48 in + 2 in = 50 inches
So she guesses he is 48 inches, but he's really 50 inches, so 50-48 = 2 inches is her error.
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Problem 2
Divide the error (2 inches) over the actual height (50 inches) to get
2/50 = 4/100 = 4%
The percentage error is 4%
This means she is 4% off the target.
Note how 4% of 50 = 0.04*50 = 2 which was the error we found back in problem 1.