how do you find the surface area of a triangle and a rectangular prism because i know that u have to add them up to get the total surface area but im stuck on those two

Match each expression with its simplified form.

Which of the following represents a number squared is equal to twenty more than nine times that number ? a) x squared = 9x + 20 b) x squared = 20x + 9 c) x squared > 9 + 20x d) x squared = 9 + x + 20

Landon wrote that 3−2.6=4. which statement about his answer is true?