1. -3x and -6x
2. 21 and -13
3. 21 and -13
4. -10b and 6b, 15 and -5
5. -20 and 30, 4c and -2c
Answer:
I believe it is e.
Step-by-step explanation:
2/5 equals 0.4, which is the same as 0.40
Answer: 
Step-by-step explanation:
Since we have given that

And we know that θ is in the Fourth Quadrant.
So, Except cosθ and sec θ, all trigonometric ratios will be negative.
As we know the "Trigonometric Identity":

It must be negative due to its presence in Fourth quadrant.
Hence, 
A numerical expression contains numbers and operations. An algebraic expression is almost exactly the same except it also contains variables.
Answer:
wait writing on a piece of paper