Answer:
(2, 4)
General Formulas and Concepts:
Pre-Algebra
Order of Operations: BPEMDAS 
- Brackets 
 - Parenthesis 
 - Exponents 
 - Multiplication 
 - Division 
 - Addition 
 - Subtraction 
 
Equality Properties 
- Multiplication Property of Equality 
 - Division Property of Equality 
 - Addition Property of Equality 
 - Subtract Property of Equality
 
Algebra I
- Solving systems of equations using substitution/elimination
 
Explanation:
Step 1: Define Systems
y = 2x
x = -y + 6
Step 2: Solve for y
Substitution
- Substitute in x: y = 2(-y + 6)
 - Distribute 2: y = -2y + 12
 - Isolate y terms: 3y = 12
 - Isolate y: y = 4
 
Step 3: Solve for x
- Define equation: x = -y + 6
 - Substitute in y: x = -4 + 6
 - Add: x = 2