Final answer:
To determine the value of an incomplete Expression #1 when r = 4 is not possible without the full expression. If it was a quadratic equation, the quadratic formula could be used by following the steps of rearranging the equation, substituting the coefficients into the formula, and calculating the solutions.
Step-by-step explanation:
In order to determine the value of Expression #1 when r = 4, we would need the complete Expression #1, which seems to be missing from the provided question. However, based on the information provided, I can give guidance on how to solve a quadratic equation using the quadratic formula. A quadratic equation takes the form at² + bt + c = 0. The quadratic formula used for solving this type of equation is t = (-b ± √(b² - 4ac)) / (2a). To use this formula:
- Rearrange the equation to match the standard form at² + bt + c = 0.
- Substitute the coefficients a, b, and c into the quadratic formula.
- Calculate the solutions for t by evaluating the expression.
Without the proper Expression #1 or its coefficients, it is impossible to continue. Please provide the complete Expression #1 for a more detailed answer.