Answer:
a=7.75
Step-by-step explanation:
19 = 4a − 12. 19+12=31. 31/4=7.75
(2 × (6cm x 9cm)) + (2 × (6cm x 5.1cm)) + (2 × (9cm x 5.1cm)) = 261 square cm
You can see how the difference between two consecutive terms is constantly increasing:




So, for the next terms we'll have to add +9, +11, +13 and so on.
Also, note that
is obtained by adding the 2nd odd number to
,
is obtained by adding the 3rd odd number to
, and so on.
So, the recursive formula is

For the explicit formula, recall that the sum of the first n odd numbers is n squared. Taking into account the fact that we're not starting from 1, we have

Answer: It is D.
Step-by-step explanation: I have taken this quiz before!
Please give me brianliest
Answer:
BC = 30
Step-by-step explanation: