Answer:
Area Δ = 102.3 units² ⇒ The answer is (d)
Step-by-step explanation:
* Use the formula of the area:
∵ Area of the triangle = 1/2 (a)(b) sin(C)
∵ We have the length of the 3 sides
∴ Use cos Rule to find the angle C
∵ cos(C) = (a² + b² - c²)/2ab
∵ a = 25 , b = 13 , c = 17
∴ cos(C) = (25² + 13² - 17²)/2(25)(13) = 625 + 169 - 289/650 = 505/650
∴ m∠C = 39°
∴ Area Δ = (1/2)(25)(13)sin(39) = 102.3 units²
∴ The answer is (d)
