Introduction:
In the given equation 4p + 7 = 19, the variable used is 'p'. A variable is a symbol or letter that represents an unknown quantity or value in an equation. It is used to generalize a mathematical statement or equation, allowing us to solve for the unknown value.

Explanation:
The equation 4p + 7 = 19 can be interpreted as "4 times a number plus 7 equals 19". In this equation, 'p' represents the unknown value or number that we need to determine. By solving the equation, we can find the value of 'p' that satisfies the given equation.

Solving the equation:
To find the value of 'p', we need to isolate the variable on one side of the equation. Here's how we can solve the equation step by step:

1. Subtract 7 from both sides of the equation to isolate the term with the variable:
4p + 7 - 7 = 19 - 7
4p = 12

2. Divide both sides of the equation by 4 to solve for 'p':
4p/4 = 12/4
p = 3

Conclusion:
The variable 'p' in the equation 4p + 7 = 19 represents an unknown number or quantity. By solving the equation, we find that the value of 'p' is 3, which satisfies the given equation. Variables are commonly used in mathematics to represent unknown values and allow us to solve equations and problems.

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