What is the area of a triangle (picture provided)

C

Step-by-step explanation:

Use the Heron's formula for the area of the triangle:

where a, b, c are lengths of triangle's sides and

Since then

Hence,

Area Δ = 6.4 units² ⇒ the answer is (c)

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 = 2 , b = 7 , c = 8

∴ cos(C) = (2² + 7² - 8²)/2(2)(7) = 4 + 49 - 64/28 = -11/28

∴ m∠C = 113.1°

∴ Area Δ = (1/2)(2)(7)sin(113.1) = 6.4 units²

the answers c

this answer is !