How do you write 8.216 in scientific notation?

Factor -8x3-2x2-12x-3 by grouping what is the resulting expression?

What is the total surface area of this square pyramid?

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