Verified Answer :

  • Isolate the variable term by adding \(16\) to both sides: \(-7a = 21\).
  • Solve for \(a\) by dividing by \(-7\): \(a = \frac{21}{-7}\).
  • Calculate the final value: \(a = -3\).
  • Final Answer: \(\boxed{-3}\).

Explanation

  1. Problem Analysis

The problem requires us to solve the linear equation \(-16 - 7a = 5\) for the variable \(a\). This equation is a simple linear relationship where we need to isolate the variable \(a\) on one side to determine its value. Our data consists of the constant \(-16\), the coefficient \(-7\) attached to \(a\), and the result of the expression, which is \(5\).

  1. Isolating the Variable Term

To solve for \(a\), we first aim to isolate the term containing \(a\). We start by adding \(16\) to both sides of the equation:
\[-16 - 7a + 16 = 5 + 16\]
Simplifying both sides:
\[-7a = 21\]

  1. Solving for 'a'

Now that we have the term \(-7a\) on the left and the constant \(21\) on the right, we solve for \(a\) by dividing both sides by the coefficient \(-7\):
\[a = \frac{21}{-7}\]
Performing the division gives us:
\[a = -3\]

  1. Verification and Final Result

To ensure our solution is correct, we can substitute \(a = -3\) back into the original equation:
\[-16 - 7(-3) = -16 + 21 = 5\]
The equation holds true, so the value of \(a\) is \(-3\). Thus, \(\boxed{-3}\).

Examples

Imagine a digital temperature controller that uses a simple linear calibration. If the current display shows \(-16\) and it needs to adjust by a factor of \(-7\) per unit change to reach a target setting of \(5\), you would solve this equation to find how many units of change are required. Understanding linear equations allows you to predict outcomes in scenarios where one quantity is proportional to another, whether in science, finance, or everyday problem solving.