Which of the following expressions CANNOT be equal to 0 when x^2 − 3x = 18 ?
Choose the correct choice from the following answers.
A) x^2 − 4x −12
B) x^2 − x − 12
C) x^2 − 3x = 18
D) x^2 − 5x − 6
E) x^2 − 4x − 21
x^2 − 3x = 18   x^2 − 3x - 18= 0   x= 6 or x= -3   All other choices result in a possibility of 0 when you plug in 6 or -3 for x   Except x^2 − 3x = 18   Answer is x^2 − 3x = 18
<result>C</result>
Which of the following expressions CANNOT be equal to 0 when x^2 − 3x = 18 ?