Adam is building a deck in his backyard around a tree. the deck is in the shape of a regular octagon. in the center of the deck, there is a hole for the tree. if a = 10.9 ft, s = 9 ft, and the diameter of the hole is equal to 7 ft, find the area of the deck to the nearest tenth of a square foot. (use 3.14 as an approximation of pi.)

Area of deck = 535.20 square feet

Step-by-step explanation:

Given : Side of regular octagon, a = 10.9 feet

Diameter of circular hole = 7 feet

So, radius of the circular hole = 3.5 feet

Area of hole = π·radius²

                     = 3.14 × (3.5)²

                     = 38.47 square feet

Therefore, Area of deck = Area of octagon - Area of hole

                                         = 573.67 - 38.47

                                        = 535.20 square feet

1) is right

step-by-step explanation:

70

step-by-step explanation: