sat suite question viewer
Advanced Math
/ Nonlinear equations in one variable and systems of equations in two variables
Difficulty: Easy
Which of the following is a solution to the equation 
?
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Explanation
Choice B is correct. Subtracting x2 from both sides of the given equation yields x2 – 4 = 0. Adding 4 to both sides of the equation gives x2 = 4. Taking the square root of both sides of the equation gives x = 2 or x = –2. Therefore, x = 2 is one solution to the original equation.
Alternative approach: Subtracting x2 from both sides of the given equation yields x2 – 4 = 0. Factoring this equation gives x2 – 4 = (x + 2)(x – 2) = 0, such that x = 2 or x = –2. Therefore, x = 2 is one solution to the original equation.
Choices A, C, and D are incorrect and may be the result of computation errors.