Answer: 
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Explanation:
Use the pythagorean trig identity
and plug in the fact that 
Isolating sine leads to
. I'm skipping the steps here, but let me know if you need to see them.
The result is negative because we're in quadrant 4, when y < 0 so it's when sine is negative.
Therefore,

Answer:
4600
Step-by-step explanation:
This is an arithmetic sequence with common difference d between consecutive terms.
d = - 2 - (- 6) = 2 - (- 2) = 6 - 2 = 4
The sum to n terms of an arithmetic sequence is
=
[ 2a + (n - 1)d ]
where a is the first term
here a = - 6, d= 4 and n = 50, hence
=
[ (2 × - 6) + (49 × 4) ]
= 25 ( - 12 + 196 )
= 25 × 184
= 4600
Answer and Step-by-step explanation:

Decreased by 20%
Answer:
b)4 11/10
Step-by-step explanation: