Question

If one root of the quadratic equation $x^2 + 2x - p = 0$ is $-2$, then the value of $p$ will be:

• A. 0
• B. 1
• C. 2
• D. 3

Hint:

If one root of a quadratic is given, substitute it directly into the equation to find the unknown parameter. This avoids unnecessary use of formulas.

Answer 1

The Correct Option is A

Step 1: Substitute the given root into the quadratic equation
The equation is: \[ x^2 + 2x - p = 0 \] Substitute $x = -2$: \[ (-2)^2 + 2(-2) - p = 0 \]

Step 2: Simplify
\[ 4 - 4 - p = 0 \] \[ 0 - p = 0 $\Rightarrow$ p = 0 \]

Step 3: Conclusion
The value of $p$ is $0$.
\[ \boxed{p = 0} \]