Do you guys know the answer to this

Answer this question, only if you know the answer. 30 points and 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

What is the slope of the line (-7,2) (4,6)