SAT Nonlinear equations in one variable and systems of equations in two variables Practice Question 4 (Easy)

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Question bank / Nonlinear equations in one variable and systems of equations in two variables

Math · Advanced MathEasy

What is the positive solution to the equation $2x^2 - 18 = 0$ ?

$3$

$6$

$9$

$81$

Show answer and explanation

Answer: A

Add 18 to both sides: $2x^2 = 18$ . Divide by 2: $x^2 = 9$ . The positive square root is $x = 3$ .

Choice C is the value of $x^2$ , not $x$ .

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