Simplify: $$x(2 x-5)+6\left(x^2-4\right)+18$$ 

Correct option is D

Given:

$$x(2 x-5)+6\left(x^2-4\right)+18$$

Solution:

$$\begin{aligned}& \Rightarrow x(2 x-5)+6\left(x^2-4\right)+18 \\& \Rightarrow 2 x^2-5 x+6 x^2-24+18 \\& \Rightarrow 8 x^2-5 x-6\end{aligned}$$

Thus, the correct answer is (d).​