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use the distributive property to solve the equation 3(x - 7) = 2x + 4 f…

Question

use the distributive property to solve the equation 3(x - 7) = 2x + 4 for x.
1.
3(x - 7) = 2x + 4
(____)(x) + (____)(-7) = 2x + 4
____x - ____ = 2x + 4
____x - __ - __ = 2x + 4 - ____
____ - ____ = 4
____ - __ + __ = 4 + ____
x = ______
multiply both terms inside the parentheses by 3.
combine like terms.
subtract 2x from both sides.
add 21 to both sides.

  1. the solution is x = ______.
  2. check. substitute the solution into the equation for x.

3(x - 7) = 2x + 4
3(____ - 7) = 2(____) + 4
3(____) = ____ + 4
____ = ____
solve 2(x + 40 + 7x) = 4x + 20 for x.
4.
2(x + 40 + 7x) = 4x + 20
2(______x + 40) = 4x + 20
2(____x) + 2(____) = 4x + 20
____x + ____ = 4x + 20
16x + 80 - ____x = 4x + 20 - ____x
____x + 80 - __ = 20 - ____
____x = ____
x = ______
combine like terms inside the parentheses.
use the distributive property.
subtract 4x from both sides.
subtract 80 from both sides.
divide both sides by 12.

  1. the solution is x = ______.

Explanation:

Solving \( 3(x - 7) = 2x + 4 \)
Step 1: Apply Distributive Property

The distributive property states \( a(b + c) = ab + ac \). For \( 3(x - 7) \), we multiply 3 by \( x \) and 3 by \( -7 \):
\( (3)(x) + (3)(-7) = 2x + 4 \)

Step 2: Simplify the Left Side

Multiply the terms:
\( 3x - 21 = 2x + 4 \)

Step 3: Subtract \( 2x \) from Both Sides

To isolate \( x \)-terms, subtract \( 2x \) from both sides:
\( 3x - 21 - 2x = 2x + 4 - 2x \)

Step 4: Combine Like Terms

Simplify both sides:
\( x - 21 = 4 \)

Step 5: Add 21 to Both Sides

To solve for \( x \), add 21 to both sides:
\( x - 21 + 21 = 4 + 21 \)

Step 6: Final Solution

Simplify:
\( x = 25 \)

Checking the Solution

Substitute \( x = 25 \) into the original equation \( 3(x - 7) = 2x + 4 \):

  1. Left side: \( 3(25 - 7) = 3(18) = 54 \)
  2. Right side: \( 2(25) + 4 = 50 + 4 = 54 \)

Both sides are equal, so \( x = 25 \) is correct.

Solving \( 2(x + 40 + 7x) = 4x + 20 \)
Step 1: Combine Like Terms Inside Parentheses

Combine \( x \) and \( 7x \):
\( 2(8x + 40) = 4x + 20 \)

Step 2: Apply Distributive Property

Multiply 2 by \( 8x \) and 2 by \( 40 \):
\( 2(8x) + 2(40) = 4x + 20 \)

Step 3: Simplify the Left Side

Multiply the terms:
\( 16x + 80 = 4x + 20 \)

Step 4: Subtract \( 4x \) from Both Sides

Isolate \( x \)-terms:
\( 16x + 80 - 4x = 4x + 20 - 4x \)

Step 5: Combine Like Terms

Simplify both sides:
\( 12x + 80 = 20 \)

Step 6: Subtract 80 from Both Sides

Isolate the \( x \)-term:
\( 12x + 80 - 80 = 20 - 80 \)

Step 7: Simplify

\( 12x = -60 \)

Step 8: Divide by 12

Solve for \( x \):
\( x = \frac{-60}{12} = -5 \)

Final Answers
  1. For \( 3(x - 7) = 2x + 4 \):
  • Distributive step: \( 3, 3 \)
  • Simplified: \( 3x - 21 \)
  • Subtract \( 2x \): \( 3x - 21 - 2x = 2x + 4 - 2x \)
  • Combine terms: \( x - 21 = 4 \)
  • Add 21: \( x - 21 + 21 = 4 + 21 \)
  • Solution: \( \boldsymbol{x = 25} \)
  1. For \( 2(x + 40 + 7x) = 4x + 20 \):
  • Combine like terms: \( 8x \)
  • Distributive step: \( 8x, 40 \)
  • Simplified: \( 16x + 80 \)
  • Subtract \( 4x \): \( 16x + 80 - 4x = 4x + 20 - 4x \)
  • Combine terms: \( 12x + 80 = 20 \)
  • Subtract 80: \( 12x = -60 \)
  • Divide: \( x = -5 \)
  • Solution: \( \boldsymbol{x = -5} \)

Answer:

Solving \( 3(x - 7) = 2x + 4 \)
Step 1: Apply Distributive Property

The distributive property states \( a(b + c) = ab + ac \). For \( 3(x - 7) \), we multiply 3 by \( x \) and 3 by \( -7 \):
\( (3)(x) + (3)(-7) = 2x + 4 \)

Step 2: Simplify the Left Side

Multiply the terms:
\( 3x - 21 = 2x + 4 \)

Step 3: Subtract \( 2x \) from Both Sides

To isolate \( x \)-terms, subtract \( 2x \) from both sides:
\( 3x - 21 - 2x = 2x + 4 - 2x \)

Step 4: Combine Like Terms

Simplify both sides:
\( x - 21 = 4 \)

Step 5: Add 21 to Both Sides

To solve for \( x \), add 21 to both sides:
\( x - 21 + 21 = 4 + 21 \)

Step 6: Final Solution

Simplify:
\( x = 25 \)

Checking the Solution

Substitute \( x = 25 \) into the original equation \( 3(x - 7) = 2x + 4 \):

  1. Left side: \( 3(25 - 7) = 3(18) = 54 \)
  2. Right side: \( 2(25) + 4 = 50 + 4 = 54 \)

Both sides are equal, so \( x = 25 \) is correct.

Solving \( 2(x + 40 + 7x) = 4x + 20 \)
Step 1: Combine Like Terms Inside Parentheses

Combine \( x \) and \( 7x \):
\( 2(8x + 40) = 4x + 20 \)

Step 2: Apply Distributive Property

Multiply 2 by \( 8x \) and 2 by \( 40 \):
\( 2(8x) + 2(40) = 4x + 20 \)

Step 3: Simplify the Left Side

Multiply the terms:
\( 16x + 80 = 4x + 20 \)

Step 4: Subtract \( 4x \) from Both Sides

Isolate \( x \)-terms:
\( 16x + 80 - 4x = 4x + 20 - 4x \)

Step 5: Combine Like Terms

Simplify both sides:
\( 12x + 80 = 20 \)

Step 6: Subtract 80 from Both Sides

Isolate the \( x \)-term:
\( 12x + 80 - 80 = 20 - 80 \)

Step 7: Simplify

\( 12x = -60 \)

Step 8: Divide by 12

Solve for \( x \):
\( x = \frac{-60}{12} = -5 \)

Final Answers
  1. For \( 3(x - 7) = 2x + 4 \):
  • Distributive step: \( 3, 3 \)
  • Simplified: \( 3x - 21 \)
  • Subtract \( 2x \): \( 3x - 21 - 2x = 2x + 4 - 2x \)
  • Combine terms: \( x - 21 = 4 \)
  • Add 21: \( x - 21 + 21 = 4 + 21 \)
  • Solution: \( \boldsymbol{x = 25} \)
  1. For \( 2(x + 40 + 7x) = 4x + 20 \):
  • Combine like terms: \( 8x \)
  • Distributive step: \( 8x, 40 \)
  • Simplified: \( 16x + 80 \)
  • Subtract \( 4x \): \( 16x + 80 - 4x = 4x + 20 - 4x \)
  • Combine terms: \( 12x + 80 = 20 \)
  • Subtract 80: \( 12x = -60 \)
  • Divide: \( x = -5 \)
  • Solution: \( \boldsymbol{x = -5} \)