LMN, NML or Angle M. Depends on context for all of these. They all work though.
Answer:
The measure of the fourth angle = 137.1°
Step-by-step explanation:
Let x = the measure of the fourth angle
Sum of all 4 interior angles in a quadrilateral equal 360°
so
x + 23.5° + 99° + 100.4° = 360°
x + 222.9° = 360°
x = 360° - 222.9°
x = 137.1°
here's the solution,
- n = 11
- a = 5 ( a = first term )
- d = 6 ( d = common difference )
we know,
=》

=》

=》

=》

=》

nth term ( 11th term ) = 65
Let's start from what we know.

Note that:

(sign of last term will be + when n is even and - when n is odd).
Sum is finite so we can split it into two sums, first

with only positive trems (squares of even numbers) and second

with negative (squares of odd numbers). So:

And now the proof.
1) n is even.
In this case, both

and

have

terms. For example if n=8 then:

Generally, there will be:

Now, calculate our sum:



So in this case we prove, that:

2) n is odd.
Here,

has more terms than

. For example if n=7 then:

So there is

terms in

,

terms in

and:

Now, we can calculate our sum:




We consider all possible n so we prove that:
Answer:

Step-by-step explanation:
the answer u will get after