2/3 + (-1/3) = 2/3 - 1/3 = 1/3
If x= -1
so.
2(-1)^2-5 / (-1 +9)
=-3/8
=-0.375
Answer:

Step-by-step explanation:
To solve this problem you must know the formula of subtraction of angles for the function cosx.
The formula is:

We can write 30° as: 45° - 15°
Then:

Using the formula for subtraction of angles we have:

Notice that we have achieved the expression shown in the statement
Finally:

Answer: 1 pound per $2
Step-by-step explanation:
Imagine this problem as a ratio:
Pounds : Dollars
3 : 6
To simplify this ratio, we see that a common divisor(in fact the only common divisor) is 3.
3/3 : 6/3
1 : 2
Therefore, we get 1 pound per $2
It is not factored completely because it was only factored by 3ab but it could have been factored by 6a²b
6a²b(a+6+8a²)