Answer:
an = a(n-1) - 7
Step-by-step explanation:
the second term is smaller than the first term 7.
a20 = a19 - 7
a19 = a18 - 7
=> a20 = (a18 - 7) - 7
Then you can accumalate until a1
-> a20 = a1 - 19*7 = 86 - 19*7 = -47
Answer:
Step-by-step explanation:
we can write -9 instead of x and y=1 instead of 1
so we write solution again
-9a+1b=-31
-9a-1b=-41
-18a=-72
a=4
we should write 4 instead of a
-9(4)+1b=-31
-36+b=-31
b=5
a=4
Answer:
a) 1/8 b) 1/6
Step-by-step explanation:
b) 6/36 = 1/6
a) 1/2 x 1/2 x 1/2 = 1/8
Answer:
yes she is right
Step-by-step explanation:3x + 3 is the same as 3 + 3x.
the zero adds nothing to the 3x term. So this means that 3x +3 and 3 + 3 are the same.
i hope this helps you.
Answer:
6561 / 128
Step-by-step explanation:
The nth term of a geometric sequence is:
a = a₁ (r)ⁿ⁻¹
The first term is 3, and the fourth term is 81/8.
81/8 = 3 (r)⁴⁻¹
27/8 = r³
r = 3/2
The eighth term is therefore:
a = 3 (3/2)⁸⁻¹
a = 6561 / 128
