Question

Solve the system by substitution.
y = -7x + 6
y = -10x​

Answer 1

x = -2

y = 20

Explanation:

y = -7x + 6

y = -10x​

y = -10x

-7x + 6 = -10x

3x = -6

x = -2

y = -7x + 6

y = -7 ( -2 ) + 6

y = 14 + 6

y = 20

Answer 2

(-2, 20)

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

y = -7x + 6

y = -10x

Step 2: Solve for x

Substitution

1. Substitute in y: -10x = -7x + 6
2. Add 10x to both sides: 0 = 3x + 6
3. Isolate x term: -6 = 3x
4. Isolate x: -2 = x
5. Rewrite: x = -2

Step 3: Solve for y

1. Define equation: y = -10x
2. Substitute in x: y = -10(-2)
3. Multiply: y = 20