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Estimate the solution to the system of equations 7x−y=7 x+2y=6 ​i need help

User Radulle
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1 Answer

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Answer:

(4/3, 7/3)

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
  • Subtraction Property of Equality

Algebra I

  • Terms/Coefficients
  • Coordinates (x, y)
  • Solving systems of equations of using substitution/elimination

Explanation:

Step 1: Define Systems

7x - y = 7

x + 2y = 6

Step 2: Rewrite Systems

Equation: x + 2y = 6

  1. [Subtraction Property of Equality] Subtract 2y on both sides: x = 6 - 2y

Step 3: Redefine Systems

7x - y = 7

x = 6 - 2y

Step 4: Solve for y

Substitution

  1. Substitute in x: 7(6 - 2y) - y = 7
  2. Distribute 7: 42 - 14y - y = 7
  3. Combine like terms: 42 - 15y = 7
  4. [Subtraction Property of Equality] Subtract 42 on both sides: -15y = -35
  5. [Division Property of Equality] Divide -15 on both sides: y = 7/3

Step 5: Solve for x

  1. Define original equation: x + 2y = 6
  2. Substitute in y: x + 2(7/3) = 6
  3. Multiply: x + 14/3 = 6
  4. [Subtraction Property of Equality] Subtract 14/3 on both sides: x = 4/3
User Nicholjs
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