Answer:
d = √13
Step-by-step explanation:
d = √((x2 - x1)² + (y2 - y1)²)
points: (-3, 8) & (-1, 5)
d = √((-1 - -3)²+(5 - 8)²)
d = √(2)²+(-3)²
d =√(4 + 9)
d = √13
Answer:
(D) 
Step-by-step explanation:
One could run this on a computer and verify the best fit through brute force. The more elegant way is, as usual, to think: What are special values of x for an exponential function? Zero, for starters - anything to the power of zero is 1. The function value for x=0 in the table is 10. Which choices A through D are close to 10 for x=0? Well, (C) and (D), the rest is too far. Next, what is the function value for the next easy one, x=1? The table says 30. Which of (C) and (D) is close to 30 for x = 1. It turns out we can safely exclude (C) because 10.84*1.77 is about 19 and that's way too far from 30. Let's check (D): 8.46*3.51=29.7 - that's quite close. Since there is no other candidate left, I bet my money on (D). Feel free to verify closeness for the other values of x if you are unconvinced yet.
1st week - Lost 3 pounds = +3
2nd week - Gained 1 pound = -1
3+13 = + 22
So 22+3 = 25 25-1 = 24
So Tina lost 24 pounds in 13 weeks.
3 x 15 = 45
3 x 14 = 42
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There are 14 packages.
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x = 42/3
-----> 3x=42