Find the exact value for sec 270 degrees

Solve this problem by using a 5d process or writing and solving an equation. no matter which method you use, be sure to define your variable and write an equation to represent the relationship a rectangle has a perimeter of 30 inches. its length is one less than three times its width what are the length and wodyh of the rectangle?

What is the surface area of the square pyramid

Which property of multiplication is shown below? if x = a + bi and y = c + di, x × y = y × x.