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Solve the system by substitution
4x+y=42
y=x+7

1 Answer

5 votes

(7, 14)

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Brackets

Parenthesis

Exponents

Multiplication

Division

Addition

Subtraction

Left to Right

Equality Properties

Algebra I

Solving systems of equations using substitution/elimination

Explanation:

Step 1: Define Systems

4x + y = 42

y = x + 7

Step 2: Solve for x

Substitution

Substitute in y: 4x + (x + 7) = 42

Combine like terms: 5x + 7 = 42

Isolate x term: 5x = 35

Isolate x: x = 7

Step 3: Solve for y

Define equation: y = x + 7

Substitute in x: y = 7 + 7

Add: y = 14

User Maxim Kovalevsky
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