Question

5x+y=9
10x-7y=-8
I need help!

Answer 1

(11/9, 26/9)

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

• Multiplication Property of Equality
• Division Property of Equality
• Addition Property of Equality
• Subtract Property of Equality

Algebra I

• Terms/Coefficients
• Solving systems of equations using substitution/elimination

Explanation:

Step 1: Define Systems

5x + y = 9

10x - 7y = -8

Step 2: Rewrite Systems

Manipulating: Equation 5x + y = 9

1. Subtract 5x on both sides: y = 9 - 5x

Step 3: Redefine Systems

y = 9 - 5x

10x - 7y = -8

Step 4: Solve for x

Substitution

1. Substitute in x: 10x - 7(9 - 5x) = -8
2. Distribute -7: 10x - 63 + 35x = -8
3. Combine like terms: 45x - 63 = -8
4. Add 63 on both sides: 45x = 55
5. Divide 45 on both sides: x = 11/9

Step 5: Solve for y

1. Define equation: 5x + y = 9
2. Substitute in x: 5(11/9) + y = 9
3. Multiply: 55/9 + y = 9
4. Isolate y: y = 26/9