What are the solutions of the equation 2 x squared equals 18? Use a graph of a related function whose roots answer the question.

Question

What are the solutions of the equation 2 x squared equals 18? Use a graph of a related function whose roots answer the question.

A. An upward facing parabola passes through points left parenthesis negative 9 comma 0 right parenthesis, left parenthesis 0 comma negative 18 right parenthesis, and left parenthesis 9 comma 0 right parenthesis.
There are two solutions: x equals plus or minus 9
B. An upward facing parabola passes through points left parenthesis negative 3 comma 0 right parenthesis, left parenthesis 0 comma negative 9 right parenthesis, and left parenthesis 3 comma 0 right parenthesis.
There are two solutions: x equals plus or minus 3
C. An upward facing parabola passes through points left parenthesis negative 2 comma 1 right parenthesis, left parenthesis 0 comma negative 3 right parenthesis, and left parenthesis 2 comma 1 right parenthesis.
There are two solutions: x equals plus or minus start root 3 end root
D. An upward facing parabola passes through points left parenthesis negative 2 comma 13 right parenthesis, left parenthesis 0 comma 9 right parenthesis, and left parenthesis 2 comma 13 right parenthesis.
There are no solutions.

Answer 1

The correct answer is B. The equation 2x^2 = 18 can be simplified to x^2 = 9, which has two solutions: x = +3 and x = -3. The graph of the related function y = 2x^2 - 18 is an upward facing parabola that passes through points (-3, 0), (0, -18), and (3, 0), as stated in option B.