Verified Answer :

  • Recognize that exponentiation has higher precedence than unary negation in the expression \(-7^2\).
  • Calculate the exponentiation: \(7^2 = 49\).
  • Apply the negation to obtain the result: \(-(49) = -49\).
  • The final result is \(\boxed{-49}\).

Explanation

  1. Analyzing the Order of Operations

To evaluate the expression \(-7^2\), we must first recognize the order of operations, often abbreviated as PEMDAS (Parentheses, Exponents, Multiplication/Division, Addition/Subtraction). In mathematical notation, an expression like \(-x^n\) is evaluated as \(-(x^n)\), which means the exponentiation is performed before the negation. If the intent was to square the negative number itself, parentheses would be used, as in \((-7)^2\).

  1. Calculating the Expression

Following the order of operations, we first perform the exponentiation on the base \(7\):
\[ 7^2 = 7 \times 7 = 49 \]
Next, we apply the negation sign to the result of this exponentiation:
\[ - (7^2) = -49 \]
Thus, the value of the expression is \(-49\).

Examples

Understanding the order of operations is crucial in everyday life, especially in fields like finance, engineering, and computer programming. For example, if a program calculates a financial deficit by squaring a loss value, misinterpreting the order of operations could lead to a massive error in the balance sheet. By strictly following mathematical conventions, we ensure accuracy in calculations, whether we are calculating compound interest, scaling dimensions in architecture, or balancing a budget. This simple rule helps prevent misinterpretations of data and keeps complex calculations consistent.