Correct Answer - Option 1 : 3/2

**Given:**

Side AB = 7 cm

BC = 8 cm

AC = 9 cm

**Identity used:**

If the sides of triangle ABC are

AB = c

BC = a

AC = b

Cosine rule;

Cos C = (a^{2} + b^{2} - c^{2})/2ab

Sec θ = 1/cos θ

**Calculation:**

In triangle ABC;

Cos C = (82 + 92 - 72)/(2 × 8 × 9)

⇒ (64 + 81 - 49)/144

⇒ 96/144 = 2/3

**∴ The value of Sec C = 3/2**