Answer:
Below in bold.
Step-by-step explanation:
First term a1 = 13
11th term a11 = a1 + 10d = 83
So a1 + 10d - a1 = 83 - 13
10d = 70
d = 10
The common difference d = 7.
Sum of n terms = (n/2)[2a1 + (n - 1)d]
Sum of the first 20 terms:
S20 = (20/2)[2*13 + (20-1)7]
S20 = 10 *(26 + 19*7)
S20 = 10*159 = 1590.
Answer:
720 ways
If you've got six cards you can arrange them in 6! ways = 720 ways.
Step-by-step explanation:
thank me later
Answer:
2
Step-by-step explanation:
because if -3 was matched up with two before then you have to make it consistent and make sure that the pattern is continous.
The speed the water level rising 250 min after the filling begins
is 1/500 m/min and it will take
2000 minutes to fill the pool. I am hoping that these answers
have satisfied your queries and it will be able to help you, and if you would
like, feel free to ask another question.
Answer:
Step-by-step explanation:
f(x) = (x - 4)(x + 2)
f(x) = x^2 + 2x - 4x - 8
f(x) = x^2 - 2x - 8