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5-7(2-x)=31-4(2x-5) help pls

1 Answer

9 votes

Answer:

x = 4

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

  1. Brackets
  2. Parenthesis
  3. Exponents
  4. Multiplication
  5. Division
  6. Addition
  7. Subtraction
  • Left to Right

Equality Properties

  • Multiplication Property of Equality
  • Division Property of Equality
  • Addition Property of Equality
  • Subtract Property of Equality

Explanation:

Step 1: Define

5 - 7(2 - x) = 31 - 4(2x - 5)

Step 2: Solve for x

  1. Distribute: 5 - 14 + 7x = 31 - 8x + 20
  2. Subtract/Add: -9 + 7x = -8x + 51
  3. Add 8x on both sides: -9 + 15x = 51
  4. Add 9 to both sides: 15x = 60
  5. Divide 15 on both sides: x = 4

Step 3: Check

Plug in x into the original equation to verify it's a solution.

  1. Substitute in x: 5 - 7(2 - 4) = 31 - 4(2(4) - 5)
  2. (Parenthesis) Multiply: 5 - 7(2 - 4) = 31 - 4(8 - 5)
  3. (Parenthesis) Subtract: 5 - 7(-2) = 31 - 4(3)
  4. Multiply: 5 + 14 = 31 - 12
  5. Add/Subtract: 19 = 19

Here we see that 19 does indeed equal 19.

∴ x = 4 is the solution to the equation.

User Matthew Pelser
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