Question

Solve by the substitution method. 6x + 8y = 0 -7x + y = 31

Answer 1

Answer:

(-4, 3)

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

1. Brackets
2. Parenthesis
3. Exponents
4. Multiplication
5. Division
6. Addition
7. Subtraction

• Left to Right

Equality Properties

Algebra I

• Solving systems of equations using substitution/elimination

Step-by-step explanation:

Step 1: Define Systems

6x + 8y = 0

-7x + y = 31

Step 2: Rewrite Systems

-7x + y = 31

1. Add 7x to both sides:                    y = 7x + 31

Step 3: Redefine Systems

6x + 8y = 0

y = 7x + 31

Step 4: Solve for x

Substitution

1. Substitute in y:                    6x + 8(7x + 31) = 0
2. Distribute 8:                        6x + 56x + 248 = 0
3. Combine like terms:           62x + 248 = 0
4. Isolate x term:                     62x = -248
5. Isolate x:                              x = -4

Step 4: Solve for y

1. Define equation:                    -7x + y = 31
2. Substitute in x:                       -7(-4) + y = 31
3. Multiply:                                  28 + y = 31
4. Isolate y:                                 y = 3