I think the answer for this question is B
A1 = 7
a(sub)n = a(sub)n-1 - 3
(sub) indicates the values touching the parenthesis are written as a subscript.
The above would be the recursive formula as you are taking the previous number and subtracting 3 to get the next number in the sequence.
Answer:
63
Step-by-step explanation:
Total groups: 21
number of students in each group: 3
total = 21 *3 =63
Answer:
its d
Step-by-step explanation:
just took the test
Step-by-step explanation:
Pythagoras' theorem for the smallest one :


= 52
Pythagoras' theorem for the middle one :
=
+ 
Pythagoras' theorem for the biggest one :


Using the formula before (for
) it becomes :



16 + 8a = 52 + 36
16+8a = 88
8a = 88-16
8a = 72
a = 9
Verifying :



= 117
The biggest one :



True