Answer:
what's the question? I don't see anything
Answer: the speed of the boat on the lake is 9 mph
Step-by-step explanation:
Let x represent the speed of the boat on the lake or in still water.
The speed of the current in a river is 6 mph. This means that if the boat goes upstream against the speed of the current, its total speed would be (x - 6)mph. If the boat goes downstream against the speed of the current, its total speed would be (x + 6)mph.
Time = distance/ speed
Every day, his route takes him 22.5 miles each way against the current and back to his dock, and he needs to make this trip in a total of 9 hours. This means that the time taken to travel upstream is
22.5/(x - 6). The time taken to travel downstream is
22.5/(x + 6)
Since the total time is 9 hours, it means that
22.5/(x - 6) = 22.5/(x + 6)
Cross multiplying, it becomes
22.5(x + 6) + 22.5(x - 6) = 9
Multiplying through by (x + 6)(x - 6), it becomes
22.5(x - 6) + 22.5(x + 6) = 9[(x + 6)(x - 6)]
22.5x - 135 + 22.5x + 135 = 9(x² - 6x + 6x - 36)
22.5x + 22.5x = 9x² - 324
9x² - 45x - 324 = 0
Dividing through by 9, it becomes
x² - 5x - 36 = 0
x² + 4x - 9x - 36 = 0
x(x + 4) - 9(x + 4) = 0
x - 9 = 0 or x + 4 = 0
x = 9 or x = - 4
Since the speed cannot be negative, then x = 9
Answer:
The 1st Blank is: A pure substance, or simply a substance
The 2nd blank on the left is: Elements
The 3rd blank on the right is: Compounds
The 4th blank which is the second middle one is: A mixture
The 5th blank which is the bottom left one is: Heterogeneous mixture
The 6th blank which is the last one on the bottom right is: Homogeneous mixture
Look at the step-by-step explanation if you get confused at the bottom.
Step-by-step explanation:
The 1st Blank: I would just put a pure substance.
The 2nd blank on the left: They are three characteristics of elements but just put elements.
The 3rd blank on the right: They are three characteristics of compounds but just put compounds.
The 4th blank which is the second middle one is: The characteristics of a mixture but just put a mixture.
The 5th blank which is the bottom left one: Are the characteristics of a heterogeneous mixture but just put heterogeneous mixture.
The 6th blank which is the last one on the bottom right: Are the characteristics of a homogeneous mixture but just put homogeneous mixture.
Answer:
2144
formula us v = 3/4 × pi × half of the diameter (radius)
Answer:
a(46) = -1.5 + 0.2(45) = -1.5 + 9 = 7.5
Step-by-step explanation:
Each term of this sequence is 0.2 greater than the previous term. The formula for this arithmetic sequence is
a(n) = -1.5 + 0.2(n - 1)
and so the 46th term is:
a(46) = -1.5 + 0.2(45) = -1.5 + 9 = 7.5
