Answer:
how many rubys are there
Step-by-step explanation:
What are the next three terms in the sequence 2, -4, 8, -16, 32, ...? A. -128, 256, -512 B. 160, 320, 640 C. 160, -320, 640 D. -
miv72 [106K]
Common ratio is -2
next 3 terms :
32 * -2 = -64
-64 * -2 = 128
128 * -2 = -256
answer is D
Answer:
(n+6)-(n-10)
Step-by-step explanation:
n is the number.
plus means addition
minus means subtraction
Answer:
10 hours
Step-by-step explanation:
(150/x) + 1.5 + (450/(x+15)) = 600/x
Multiply through by x(x + 15):
150(x + 15) + 1.5x(x + 15) + 450x = 600(x + 15)
150x + 2250 + 1.5x^2 + 22.5x + 450x = 600x + 9000
150x + 2250 + 1.5x^2 + 22.5x + 450x - 600x - 9000 = 0
1.5x^2 + 22.5x - 6750 = 0
x = (-22.5 +/- sqrt(22.5^2 - 4(1.5)(-6750))) / (2*1.5)
x = (-22.5 +/- sqrt(506.25 + 40500)) / 3
x = (-22.5 +/- sqrt(41006.25)) / 3
x = (-22.5 +/- 202.5) / 3
x = 180/3 or -225/3
x = 60 or -75
But a negative number doesn't make sense, so therefore x = 60, so the journey took 600/60 = 10 hours.
