Correct Answer - Option 1 : 3x – 4y + 12 = 0

**Concept****:**

The equation of tangent of parabola

**y**^{2} = 4ax at the point (x_{1}, y_{1}) is given by: yy_{1} = 2a (x + x_{1})

**Calculation****:**

**Given:**

Equation of parabola is **y2 = 9x**

Let point P = (4, 6)

Here, a = \(\frac94\), x_{1} = 4 and y_{1} = 6.

As we know that, the equation of tangent of parabola y2 = 4ax at the point (x1, y1) is given by: yy1 = 2a (x + x1).

⇒ 6y = \(\frac{9(x + 4)}2\)

⇒ 12y = 9x + 36

⇒ 3x – 4y + 12 = 0

Hence, **the equation of required tangent is: 3x – 4y + 12 = 0**