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1 vote
4x - 2y = -20
7x + 2y = -2

User Sbaechler
by
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1 Answer

4 votes

Answer:

(-2, 6)

General Formulas and Concepts:

Pre-Algebra

  • Order of Operations: BPEMDAS
  • Equality Properties

Algebra I

  • Solving systems of equations using substitution/elimination
  • Solving systems of equations by graphing

Explanation:

Step 1: Define systems

4x - 2y = -20

7x + 2y = -2

Step 2: Rewrite systems

4x - 2y = -20

  1. Add 2y to both sides: 4x = 2y - 20
  2. Divide 4 on both sides: x = 1/2y - 5

Step 3: Redefine systems

x = 1/2y - 5

7x + 2y = -2

Step 4: Solve for y

Substitution

  1. Substitute in x: 7(1/2y - 5) + 2y = =-2
  2. Distribute 7: 7/2y - 35 + 2y = -2
  3. Combine like terms: 11/2y - 35 = -2
  4. Add 35 to both sides: 11/2y = 33
  5. Isolate y: y = 6

Step 5: Solve for x

  1. Define original equation: 7x + 2y = -2
  2. Substitute in y: 7x + 2(6) = -2
  3. Multiply: 7x + 12 = -2
  4. Subtract 12 on both sides: 7x = -14
  5. Divide 7 on both sides: x = -2

Step 6: Graph systems

Check the system.

4x - 2y = -20 7x + 2y = -2-example-1
User Nichelle
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4.9k points