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2 years ago

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

Mathematics

1 answer:

Over [174]2 years ago

6 0

Answer:

x = 4

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right

Equality Properties

Step-by-step explanation:

Step 1: Define Equation

7(2x - 5) = 21

Step 2: Solve for x

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

Step 3: Check

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

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

Here we see that 21 does indeed equal 21.

∴ x = 4 is the solution to the equation.

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aksik [14]

Answer:

The answer is "120".

Step-by-step explanation:

Given values:

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3 years ago

What does and 6 7/12 yards x 3 1/6 = ?

aleksandr82 [10.1K]

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3 years ago

Maggie is displaying paperback and hardback books on her book shelf. The ratio of hardback books to total books is 5 to 13. Whic

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Answer:

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Step-by-step explanation:

Let

The total books are = 13x ; where x is any positive number

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2 years ago

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3 years ago

Read 2 more answers

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Klio2033 [76]

Answer:

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