Which of the following is a linear equation in one variable?

Class 7Simple EquationsSimple Equations

Step-by-Step Solution

Linear in one variable: variable to the first power, only one variable.

3 x + 5 = 14

fits. The others have

x^{2}

, two variables, or

\frac{1}{x}

Answer: A)

3 x + 5 = 14

When the variable appears on both sides, gather all variable terms on one side and all constants on the other.

Example:

5 x + 3 = 2 x + 18

.
Move

2 x

to the left (flip):

5 x - 2 x + 3 = 18

Simplify:

3 x + 3 = 18

Move +3:

3 x = 15

Divide:

x = 5

.

**Verify**:

5 (5) + 3 = 28

;

2 (5) + 18 = 28

✓.

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