7p - [3q - {8p - (4q - 10p)}] = ?
25p - 7q
We need to simplify the given algebraic expression: \(7p - [3q - \{8p - (4q - 10p)\}]\).
To simplify this expression, we will follow the order of operations, often remembered by acronyms like BODMAS or PEMDAS, which means we simplify the parts inside the brackets, then the curly braces, and finally the square brackets.
The innermost part is \((4q - 10p)\). There are no like terms or operations to perform inside, so we remove the parentheses. The expression becomes:
\(7p - [3q - \{8p - (4q - 10p)\}] = 7p - [3q - \{8p - 4q + 10p\}]\)
Note that the negative sign before the parentheses is distributed to both terms inside.
The expression inside the curly braces is \(\{8p - 4q + 10p\}\). We can combine the like terms involving \(p\): \(8p + 10p = 18p\).
So, the expression inside the curly braces simplifies to \(\{18p - 4q\}\).
The main expression now looks like:
\(7p - [3q - \{18p - 4q\}]\)
The expression inside the square brackets is \([3q - \{18p - 4q\}]\). We need to remove the curly braces, remembering to distribute the negative sign before them.
\([3q - (18p - 4q)] = [3q - 18p + 4q]\)
Now, combine the like terms inside the square brackets, which are the terms involving \(q\): \(3q + 4q = 7q\).
So, the expression inside the square brackets simplifies to \([7q - 18p]\).
The main expression is now:
\(7p - [7q - 18p]\)
Finally, we remove the square brackets. Again, distribute the negative sign before the square brackets to each term inside.
\(7p - (7q - 18p) = 7p - 7q + 18p\)
Combine the like terms, which are the terms involving \(p\): \(7p + 18p = 25p\).
The simplified expression is \(25p - 7q\).
Let's summarize the steps:
The simplified form of the expression \(7p - [3q - \{8p - (4q - 10p)\}]\) is \(25p - 7q\).
| Concept | Description | Example |
|---|---|---|
| Like Terms | Terms that have the same variables raised to the same powers. | \(3x\) and \(5x\), \(2y^2\) and \(-7y^2\). Unlike terms: \(3x\) and \(5y\). |
| Combining Like Terms | Adding or subtracting the coefficients of like terms. | \(3x + 5x = 8x\), \(2y^2 - 7y^2 = -5y^2\). |
| Order of Operations (BODMAS/PEMDAS) | Rules for the sequence of operations in an expression: Brackets/Parentheses, Orders/Exponents, Division/Multiplication, Addition/Subtraction. | Simplify expressions within brackets first. |
| Distributive Property | Multiplying a term by an expression in parentheses means multiplying the term by each term inside the parentheses. \(a(b+c) = ab + ac\). | \(-2(x+3) = -2x - 6\). \(-(a-b) = -a + b\). |
When simplifying expressions with nested brackets like parentheses \(()\), curly braces \(\{\}\), and square brackets \(\{\}\), it is standard practice to work from the innermost set of grouping symbols outwards. This ensures that the operations within each level are correctly evaluated before they are affected by operations or signs outside.
Always be careful when distributing a negative sign (\(-\)) or a number outside a set of brackets. The sign or number must be multiplied by every term inside those brackets.
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