Answer:
364/27
Step-by-step explanation:
9, 3, 1, ... is a geometric sequence with common ratio r = 1/3.
The nth term is a1rn-1.
If a1rn-1 = 1/27, then 9(1/3)n-1 = 1/27
32(3-1)n-1 = 3-3
3231-n = 3-3
33-n = 3-3
3-n = -3
n = 6
The sum, Sn, of the first n terms of a geometric sequence is given by Sn = a1(1 - rn) / (1 - r).
So, 9 + 3 + 1 + ... + 1/27 = S6 = 9(1 - (1/3)6) / (1 - 1/3)
= 9(1 - 1/729) / (2/3)
= (27/2)(728/729) = 364/27
Answer:
x=2
HPT 3x+5y=6 (1) và 2x+y=4 (2)
Nhân phương trình (2) với 5 để hệ số y của 2 phương trình bằng nhau. Ta có:
(2)⇔ 10x+5y=20(3)
Trừ (3) cho (1), có: 7x+0y=14⇒x=2
Answer:
just here for points
Step-by-step explanation:
Answer: arc ef is 68
Step-by-step explanation:
Since EF and FG are the same length (given)
and DE and DG are the same length (both are radius of the circle)
and DF is a shared side, the 2 inscribed triangles are congruent, making angle EDF also 68
The measure of an arc is the same as the measure of the angle across from it
Q + d = 16....q = 16 - d
0.25q + 0.10d = 3.10
0.25(16 - d) + 0.10d = 3.10
4 - 0.25d + 0.10d = 3.10
-0.25d + 0.10d = 3.10 - 4
-0.15d = -0.90
d = -0.90/-0.15
d = 6...dimes
q + d = 16
q + 6 = 16
q = 16 - 6
q = 10...quarters
so there are (10 - 6) = 4 more quarters then dimes
