Help!! I need to get this done.

What is the area of triangle abc if a = 8, b = 11, and c = 15?

With this one. will mark brainliest

[15 points]find the least common multiple of the expressions: 1. 3x^2, 6x - 18 2. 5x, 5x(x +2) 3. x^2 - 9, x + 3 4. x^2 - 3x - 10, x + 2 explain if possible