Factor: (please tell me steps)
9x^(4)+21x^(3)-9x^(2)-21x

What's the difference between: x≥0 and nonnegative integer. ?

Show your workcan a right triangle have this sides? *how to prove it without using the pythagorean theorema*

In each of the cases that follow, the magnitude of a vector is given along with the counterclockwise angle it makes with the +x axis. use trigonometry to find the x and y components of the vector. also, sketch each vector approximately to scale to see if your calculated answers seem reasonable. (a) 50.0 n at 60.0°, (b) 75 m/ s at 5π/ 6 rad, (c) 254 lb at 325°, (d) 69 km at 1.1π rad.