Question

Find the solution to the system of equations below. 7x+3y=12 and 7x-3y=30

A.(7, 3)
B.(-3, 3)
C.3, -3)
D.(2, -2)

Answer 1

C. (3, -3)

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

7x + 3y = 12

7x - 3y = 30

Step 2: Solve for x

1. Eliminate y: 14x = 42
2. Isolate x: x = 3

Step 3: Solve for y

1. Substitute in x: 7(3) + 3y = 12
2. Multiply: 21 + 3y = 12
3. Isolate y term: 3y = -9
4. Isolate y: y = -3

And we have our final answer!