Question

7(2x-5)=21 What is x?

Answer 1

Answer:

x = 4

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

Step-by-step explanation:

Step 1: Define Equation

7(2x - 5) = 21

Step 2: Solve for x

1. Distribute 7:                   2x - 5 = 3
2. Isolate x term:                2x = 8
3. Isolate x:                         x = 4

Step 3: Check

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

1. Substitute in x:                  7(2(4) - 5) = 21
2. Multiply:                             7(8 - 5) = 21
3. Subtract:                            7(3) = 21
4. Multiply:                             21 = 21

Here we see that 21 does indeed equal 21.

∴ x = 4 is the solution to the equation.