What is the value of the expressionbn8 + (9 x n ) when n =5?

Which expressions are equivalent to -6 + 3m

The square pyramid has a volume of 441 cubic inches. what is the value of x? 1/7x is the height x is the base

When keisha installed a fence along the 200 foot perimeter of her rectangular back yard, she left an opening for a gate.in the diagram below, she used x to represent the length in feet of the gate? what is the value? a. 10 b. 20 c. 25 d. 30