Question

nancy found that x=1 is one solution to the quadratic equation (x+2)²=a. what is the value of a?
○ -9
○ -3
○ 3
○ 9

Explanation:

Step1: Substitute x=1 into the equation

We know that \( x = 1 \) is a solution to the equation \( (x + 2)^2=a \). So we substitute \( x = 1 \) into the left - hand side of the equation.
\( (1 + 2)^2=a \)

Step2: Calculate the left - hand side

First, calculate the value inside the parentheses: \( 1+2 = 3 \). Then, square the result: \( 3^2=9 \). So \( a = 9 \).

Answer:

9