Question

Solve the given system by substitution.

Answer 1

-4(2) + 3 = -5
8 - 1 = 7

Answer 2

(-2/3, -23/3)

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

Explanation:

Step 1: Define Systems

-4p + q = -5

p - q = 7

Step 2: Rewrite Systems

p - q = 7

1. Add q on both sides: p = q + 7

Step 3: Redefine Systems

-4p + q = -5

p = q + 7

Step 4: Solve for q

Substitution

1. Substitute in p: -4(q + 7) + q = -5
2. Distribute -4: -4q - 28 + q = -5
3. Combine like terms: -3q - 28 = -5
4. Isolate q term: -3q = 23
5. Isolate q: q = -23/3

Step 5: Solve for p

1. Define equation: p - q = 7
2. Substitute in q: p - (-23/3) = 7
3. Simplify: p + 23/3 = 7
4. Isolate p: p = -2/3