Let's break down each sentence into algebraic expressions:

a) Double a number and add three.

• Let the number be represented as $x$.
• "Double a number" means multiplying the number by 2, and "add three" means adding 3.
• The algebraic expression:
  $2x + 3$

b) Subtract five from a number, then multiply by two.

• Let the number be represented as $x$.
• "Subtract five from a number" means $x - 5$, and "then multiply by two" means multiplying the result by 2.
• The algebraic expression:
  $2(x - 5)$

c) Divide a number by seven, then add six.

• Let the number be represented as $x$.
• "Divide a number by seven" means $\frac{x}{7}$, and "then add six" means adding 6 to the result.
• The algebraic expression:
  $\frac{x}{7} + 6$

d) A number is subtracted from twenty-eight.

• Let the number be represented as $x$.
• "A number is subtracted from twenty-eight" means subtracting $x$ from 28.
• The algebraic expression:
  $28 - x$

e) Twenty-eight is subtracted from a number.

• Let the number be represented as $x$.
• "Twenty-eight is subtracted from a number" means subtracting 28 from $x$.
• The algebraic expression:
  $x - 28$

Would you like a more detailed explanation of any of these expressions, or do you have more questions?

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Here are some related questions for you:

1. How would you express "Triple a number and subtract five" algebraically?
2. Can you write an algebraic expression for "Add four to a number, then divide by two"?
3. How would you translate "Subtract a number from fifteen, then multiply by three" into an algebraic expression?
4. What is the algebraic expression for "Half of a number, increased by seven"?
5. How do you express "Five less than the product of two numbers" algebraically?

Tip: When translating sentences into algebraic expressions, look for key operations like "add," "subtract," "multiply," or "divide," and identify the numbers involved.