The 4 is in the tenth place...so you have to look at the number beside it to see if you round up or down. It's a 6, which is greater than 5 so you round up.
3.5
The expression for the perimeter would be
2(x) + 2(2x+7)
which can be simplified to 2x+4x+14
which equals 6x+14
Csc a - sin a = cos a cot a
1/sin a - sin a = cos a (cos a / sin a)
(1 - sin^2 a)/sin a = cos^2 a/sin a
cos^2 a/sin a = cos^2 a/sin a
Therefore, the given equation is an identity.
Answer:
I believe its the second one but i could be wrong