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3 years ago

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

Mathematics

1 answer:

jekas [21]3 years ago

7 0

Answer:

(-4, 3)

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
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

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

Step 3: Redefine Systems

6x + 8y = 0

y = 7x + 31

Step 4: Solve for x

Substitution

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

Step 4: Solve for y

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

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