Solve the inequality [tex]-2x^2 + 12x \ \textgreater \ 18[/tex]

A. [tex]x \ \textless \ 3[/tex]
B. [tex]x \ \textgreater \ 3[/tex]
C. [tex]x \ \textgreater \ -3[/tex]
D. No solutions



Answer :

To solve the inequality \(-2x^2 + 12x > 18\), let's follow the necessary steps for working with quadratic inequalities:

1. Rewrite the inequality in standard form:
\(-2x^2 + 12x > 18\)

2. Move all terms to one side to set it to zero:
[tex]\[ -2x^2 + 12x - 18 > 0 \][/tex]

3. Factor the quadratic expression, if possible:
First, recognize that the quadratic expression is
[tex]\[ -2(x^2 - 6x + 9) \][/tex]
Since, \(x^2 - 6x + 9 = (x - 3)^2\), we can rewrite the inequality as
[tex]\[ -2(x - 3)^2 > 0 \][/tex]

4. Analyze the factored form:
\((x - 3)^2\) is a perfect square and it is always non-negative, meaning \((x - 3)^2 \geq 0\). However, it can never be greater than zero when scaled by a negative coefficient \(-2\), since
[tex]\[ -2(x - 3)^2 \leq 0 \][/tex]
And the expression \(-2(x - 3)^2\) is exactly zero when \(x = 3\), leading to no solutions where \(-2(x - 3)^2 > 0\).

5. Conclusion:
Because \(-2(x - 3)^2\) always evaluates to zero or negative and never strictly positive, there are no values of \(x\) which satisfy \(-2x^2 + 12x > 18\).

Thus, the correct answer is:
[tex]\[ \text{D. no solutions} \][/tex]