Question

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

Answer 1

Answer:

C. (3, -3)

General Formulas and Concepts:

Pre-Algebra

• Order of Operations: BPEMDAS
• Equality Properties

Algebra I

• Solving systems of equations using substitution/elimination

Step-by-step 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!