Answer:
20x²+180x + 405
Step-by-step explanation:
Follow PEMDAS to know what you do first
square (2x + 9) by foiling
(2x+9) (2x + 9)
= 4x²+ 36x + 81
Multiply by 5
20x²+180x + 405
ANSWER: x = 130°
EXPLANATION: You must add given angles and then subtract from 180°.
Answer:

Step-by-step explanation:
Surface area → area of 2 bases + area of 6 rectangles
Area of base is given
Area of rectangle → length × width
