Colin is 9 years older than Richard. David is 12 years younger than Richard. If the total of their ages is 93, how old is the eldest of them?

What is the value of x in the this question ?

Click an item in the list or group of pictures at the bottom of the problem and, holding the button down, drag it into the correct position in the answer box. release your mouse button when the item is place. if you change your mind, drag the item to the trashcan. click the trashcan to clear all your answers. solve this quadratic equation using the quadratic formula. 2x2 - 2x=1 need asap

The two square pyramids are similar. find the total volume of both pyramids if the ratio of their surface areas is 9/16