Answer:
see explanation
Step-by-step explanation:
(8)
the common ratio r, of a geometric sequence is
r =
=
= ......
r =
=
= 8
(9)
The simplest way to evaluate the sum is to substitute k = 3, 4, 5, 6 into each term and sum them
(- 9 + 20) + (- 12 + 20) + (- 15 + 20) + (- 18 + 20)
= 11 + 8 + 5 + 2 = 26
Answer:
a = 40°
Step-by-step explanation:
I. When total angle is 180 or half of circle
Find a or missing angle by
180 = 50 + 90 + x
180 - 140 = x
x = 40º
That makes a is 40º
Hope that help :)
Answer: x ( y + 1) + y ( y + 3) + 2
Step-by-step explanation:
( x + y + 2) ( y + 1)
x ( y + 1) + y ( y + 1) + 2 ( y + 1)
expanding the bracket
( xy + x) + ( y2 + y) + ( 2y + 2)
removing the bracket
xy + x + y2 +y + 2y + 2
collecting like terms
xy + x + y2 + 3y + 2
given as: x(y + 1) + y ( y + 3) + 2
Answer:
Step-by-step explanation:
You just need the distance formula here. It's very simple to follow:

which, for us, looks like this:
and
and
and
so
d = 15