Verified Answer :

  • Identify the polynomial expression to be simplified: \((-x - 6) - (-x^2 + 4)\).
  • Convert the subtraction to an addition by distributing the negative sign, resulting in \(-x - 6 + x^2 - 4\).
  • Group like terms by degree to get \(x^2 - x + (-6 - 4)\).
  • Combine constants and arrange in descending order to reach the final expression \(\boxed{x^2 - x - 10}\).

Explanation

  1. Problem Analysis and Conceptual Approach

To simplify the expression \((-x - 6) - (-x^2 + 4)\), we first identify the individual components. The expression consists of a linear part, \(-x - 6\), and a quadratic part, \(-x^2 + 4\), which we are subtracting. Using algebra tiles, we imagine \(-x^2\)-tiles, \(-x\)-tiles, and negative constant unit tiles. Subtracting a polynomial is equivalent to adding its additive inverse, which means we change the sign of every term inside the second polynomial.

  1. Applying the Additive Inverse

When we subtract the second polynomial \((-x^2 + 4)\), we distribute the negative sign across its terms: \(-(-x^2) = x^2\) and \(-(4) = -4\). Now, the original expression can be rewritten as a addition problem: \(-x - 6 + x^2 - 4\). This approach allows us to group like terms more efficiently.

  1. Combining Like Terms

Now we group the terms by their degree:

  • Quadratic term: \(x^2\)
  • Linear term: \(-x\)
  • Constant terms: \(-6 - 4\)

Combining these results, we get the \(x^2\) term, the \(-x\) term, and the constant \(-10\). Writing the polynomial in descending order of powers, we obtain \(x^2 - x - 10\).

  1. Final Result

After simplifying, the expression \((-x - 6) - (-x^2 + 4)\) results in the standard polynomial form: \(\boxed{x^2 - x - 10}\).

Examples

Algebra tiles are not just for paper-and-pencil math; they represent a fundamental way to visualize how quantities interact. Imagine you are managing a warehouse where you track positive inventory (incoming stock) and negative inventory (outgoing orders or debts). If you have a current status of \(-x - 6\) and you need to remove a negative order of \(-x^2 + 4\), subtracting this negative order effectively increases your positive assets. Learning to combine these terms is the basis for algebraic modeling in economics, physics, and engineering.