Answer:
Help with what Question?
Step-by-step explanation:
What Question do you need help with?
Answer:
y = - 7.5
Step-by-step explanation:
Given
- 140 = 18 + 4(5y - 2) ← distribute and simolify right side
- 140 = 18 + 20y - 8
- 140 = 10 + 20y ( subtract 10 from both sides )
- 150 = 20y ( divide both sides by 20 )
- 7.5 = y
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Define x:
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Let x be the number of students in the second class:
⇒second class = x
There are 3 more students in the first class than in the second class:
⇒first class = x + 3
There are 2 more students in the third class than in the second class:
⇒third class = x + 2
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Expression for each class:
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First class = x + 3
Second class = x
Third class = x + 2
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Expression for total number of students:
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Total = x + 3 + x + x + 2
Total = 3x + 5
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Find x:
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There are 80 students in total, so
3x + 5 = 80
3x = 75
x = 25
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Find the number of students in each class:
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First class = x + 3 = 25 + 3 = 28
Second class = x = 25
Third class = x + 2 = 25 + 2 = 27
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Answer: There are 25 students in the second class.
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Answer:
18 inches
Step-by-step explanation:
Given
--- radius
--- distance between chord and the center of the circle
Required
The chord length
See attachment for illustration
First, calculate distance AX using Pythagoras theorem.

This gives:


Collect like terms


Take square roots of both sides

AB is then calculated as:

Where:

So:


The side of a cube when the diagonal is known is found using the formula:
Side = √3 * diagonal/3
Replace diagonal with 20:
Side = √3 * 20/3
Side = √3 * 6 2/3
Side = 11.547 cm (Round the answer as needed).