Answer:
1089
Step-by-step explanation:
The original number is A0CD, We have that DC0A = 9 x A0CD.
If A =1, then D = 9 and we have:
9C01 = 9 x 10C9
In order for this expression to be true, the following must also be true:
(C x 9) + 8 must be divisible by 10, which means that C x 9 must end in a 2.
The only multiple of 9 (from 9 to 81) that ends in a 2 is 72.
72 = 9 x 8.
Therefore, C must be 8 and the original number is 1089. Multiply it by 9 to check the answer:
1089 x 9 = 9,081
Therefore, 1089 is correct.
Answer:
8 + 18+ 28+ 38+ 48= 140
Step-by-step explanation:
In this problem you use cosine because you know the hypotenuse and you want to know the adjacent side of the triangle. So in your calculator you would input cos(52). Then you would multiply that answer with the hypotenuse side. So your equation would be this: cos(52) x 13
Answer:
11/2, 22/4, 33/6, 44/8, 55/10, 66/12, 77/14, 88/16, 99/18, 110/20, 121/22, 132/24, 143/26, 154/28, 165/30, 176/32, 187/34, 198/36, 209/38, 220/40, and so on ...