Question

PLEASE HELP FAST! Solve for Y in the following system of equations!

Answer 1

Answer:

B.) 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

x - y = -1

3x + 5y = 21

Step 2: Rewrite Systems

x - y = -1

1. Add y to both sides:                    x = y - 1

Step 3: Redefine Systems

x = y - 1

3x + 5y = 21

Step 4: Solve for y

Substitution

1. Substitute in x:                              3(y - 1) + 5y = 21
2. Distribute 3:                                   3y - 3 + 5y = 21
3. Combine like terms:                     8y - 3 = 21
4. Add 3 to both sides:                     8y = 24
5. Divide 8 on both sides:                y = 3