Is the square root of negative 64 rational or irrational

Find the sum of the first 8 terms of the following sequence. round to the nearest hundredth if necessary.

If w = 6 units, x = 3 units, and y = 5 units, what is the surface area of the figure? 168 units2 240 units2 144 units2 96 units2

Solve for x: 5/3 x = 20/21 it's fraction. remember to simplify your fraction