Question

20(x+9)=140
solve for x

Answer 1

x = -2

Explanation:

20(x+9)=140

divide both sides by 20

x + 9 = 7

move the 9

x = 7 - 9

x = -2

Answer 2

x = -2

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

Explanation:

Step 1: Define

20(x + 9) = 140

Step 2: Solve for x

1. Divide 20 on both sides: x + 9 = 7
2. Subtract 9 on both sides: x = -2

Step 3: Check

Plug in x into the original equation to verify it's a solution.

1. Substitute in x: 20(-2 + 9) = 140
2. (Parenthesis) Add: 20(7) = 140
3. Multiply: 140 = 140

Here we see that 140 does indeed equal 140.

∴ x = -2 is the solution to the equation.