If an is a5
and
an-1 is a4
then using your recursive formula for an arithmetic sequence
an=an-1 +d
then
a5=a4+d
now, a4 =6 and common difference "d" is d=-11
hence
a5=6 -11
6-11= -5
any questions?
Answer:

Step-by-step explanation:
Given the expression 
According to the law of logarithm;
loga + log b = log(ab) and log a - log b = log(a/b)
The given expression becomes;

Answer:
<em>Since one of the angles is 90°, the triangle is right.</em>
Step-by-step explanation:
<u>Angles in a Triangle</u>
The sum of angles in a triangle is 180°. We are given the angles are x, 5x, and 6x, thus:
x + 5x + 6x = 180
Simplifying:
12x = 180
Dividing by 12:
x = 180/12 = 15
x = 15°
5x = 75°
6x = 90°
Since one of the angles is 90°, the triangle is right.
I'm not 100 percent sure I think d
Answer:
It's a total increase by 27,65%
Step-by-step explanation:
1,11 × 1,15 = 1,2765
1,2765 = +27,65%