Answer:
1083 seats
Step-by-step explanation:
this is an arithmetic sequence :
an = an-1 + c
in our case
a1 = 10 (10 seats in the first row)
a2 = a1 + 1 = 10 + 1 = 11
a3 = a2 + 1 = a1 + 1 + 1 = 10 + 1 + 1 = 12
an = an-1 + 1 = a1 + (n-1)×1 = a1 + n - 1 = 10 + n - 1 = 9 + n
a38 = a1 + 37 = 10 + 37 = 47 seats.
altogether this means the sum of the arithmetic sequence of a1 to a38.
the general sum of an arithmetic sequence from a1 to an is
n×(a1 + an)/2
in our case
38×(10 + 47)/2 = 19×57 = 1083 seats
Answer:
(4x + 12 ) - ( -8 ) =
4x + 20
Explanation:
Just add them up and form a equation ( this is for the second one )
25÷100=0.25
0.25×680=170 is the answer
Answer:
The hinge theorem states that if two sides of one triangle are congruent to two sides of another triangle, and the included angle of the first is larger than the included angle of the second, then the third side of the first triangle is longer than the third side of the second triangle
Step-by-step explanation: