David is making patterns using these rules. Rule for Pattern A: start with 20 and subtract 2 Rule for Pattern B: start with 10 and subtract 1 Which patterns did David make?

20,18,16,14,12,10,8,6,4,2

10,9,8,7,6,5,4,3,2,1

Step-by-step explanation:

Pattern A:

Rule : start with 20 and subtract 2

Pattern B:

Rule : Start with 10 and subtract 1

Pattern 1:

20 - 2 = 18

18 - 2 = 16

16 - 2 = 14

14 - 2 = 12

12 - 2 = 10

10 - 2 = 8

8 - 2 = 6

6 - 2 = 4

4 - 2 = 2

20,18,16,14,12,10,8,6,4,2

Pattern 2:

10 - 1 = 9

9 - 1 = 8

8 - 1 = 7

7 - 1 = 6

6 - 1 = 5

5 - 1 = 4

4 - 1 = 3

3 - 1 = 2

2 - 1 = 1

10,9,8,7,6,5,4,3,2,1

b

step-by-step explanation:

the answer is  

a.

28 ft2

step-by-step explanation: