Answer:
x=# of boys
x+7=# of girls
x+x+7=25
2x+7=25
2x=25-7
2x=18
x=18/2
x=9 boys
x+7=16 girls
If you don't understand variables use trial and error.
Boys Girls
1 8
2 9
3 10
4 11
5 12
6 13
7 14
8 15
9 16 9+16=25 students
You could start this way...
Boys Girls
12 13
11 14
10 15
9 16 16 is 7 more than 9
If you would like to solve the equation - 2/5 * x + 6 = 8, you can do this using the following steps:
- 2/5 * x + 6 = 8
- 2/5 * x = 8 - 6
- 2/5 * x = 2 /*(-5/2)
x = 2 * (- 5/2)
x = - 5
The correct result would be -5.
Answer:

General Formulas and Concepts:
<u>Calculus</u>
Limits
- Limit Rule [Variable Direct Substitution]:

Differentiation
- Derivatives
- Derivative Notation
The definition of a derivative is the slope of the tangent line: 
Step-by-step explanation:
<u>Step 1: Define</u>
<em>Identify.</em>
<em />
<u>Step 2: Differentiate</u>
- [Function] Substitute in <em>x</em>:

- Substitute in functions [Definition of a Derivative]:

- Simplify:

- Evaluate limit [Limit Rule - Variable Direct Substitution]:

- Simplify:

∴ the derivative of the given function will be equal to 4 divided by x².
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Learn more about derivatives: brainly.com/question/25804880
Learn more about calculus: brainly.com/question/23558817
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Topic: AP Calculus AB/BC (Calculus I/I + II)
Unit: Differentiation
€1 = $1.10
€90 = $99
$99 - $63 = $36
$36 / $1.20 = $30
$36 = €30
Answer €30
We have no idea how much is one faithful of a barrel.