Multiplying polynomial expressions!

3x(2x²-4x+9)

Please show work

What are the soultion(s) to the quadratic equation 40- x^2=0

Which basic geometric term has no width, no length, and no thickness? line b. point c. angle d. plane

Ireally need subtract and simplify.(-y^2 – 4y - 8) – (-4y^2 – 6y + 3)show your work, ! i will mark you brainliest but you have to show your work.