Explanation

(b)
Given curve is $y = 2x^{2} - x + 1$
On differentiating w.r.t. $x$, we get
$\frac{dy}{dx} = 4x - 1$
Since, this is parallel to the given curve $y = 3x + 9$
$\therefore$ These slopes are equal
$\Rightarrow \ \ 4x - 1 = 3\ \ \Rightarrow \ \ x = 1$
At $x = 1,\ \ y = 2(1)^{2} - 1 + 1\ \ \Rightarrow y = 2$
Thus, the point is (1, 2).