Find the Distance Between Two Points
Use the distance formula to determine the distance between two points.
Exact Form:
√85
Decimal Form:
9.21954445
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I have memorized facts about fractions like these, so can tell you ...

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A fraction with 9 as a denominator is a repeating 1-digit decimal with the decimal digit being the numerator of the fraction.
A fraction with 11 as a denominator is a repeating 2-digit decimal with the two digits being 9 times the numerator of the fraction.
1/8 = 0.125, so any multiple of 1/8 is that multiple of 0.125.
Look at points (0, -1) and (1, 5).
m = (y2 - y1)/(x2 - x1) = (5 - (-1))/(1 - 0) = 6/1 = 6
Slope = 6
Answer: 6
120/4 is 30
You'll be able to put 4 nails thirty times.
You put them every 6 feet
So, you have 5 feet before running out.
The one who walked 1.2 miles would have made $72 and the one who walked 0.8 miles would have made $48.