Question

Solve each equation by substitution

y = 3x + 4
y = 6x + 1

Options

• (7, 1)
• (1, 7)
• (-2, 4)
• (1, -7)​

Answer 1

(1, 7)

Explanation:

y = 3x + 4

y = 6x + 1

6x + 1 = 3x + 4 ⇒ x = 1

y = 3(1) + 4 = 7

(1, 7)

Answer 2

(1, 7)

General Formulas and Concepts:

Pre-Algebra

• Order of Operations: BPEMDAS
• Equality Properties

Algebra I

• Solving systems of equations using substitution/elimination

Explanation:

Step 1: Define systems

y = 3x + 4

y = 6x + 1

Step 2: Solve for x

1. Substitute in y: 3x + 4 = 6x + 1
2. Subtract 3x on both sides: 4 = 3x + 1
3. Subtract 1 on both sides: 3 = 3x
4. Divide 3 on both sides: 1 = x
5. Rewrite: x = 1

Step 3: Solve for y

1. Define original equation: y = 6x + 1
2. Substitute in x: y = 6(1) + 1
3. Multiply: y = 6 + 1
4. Add: y = 7