Answer:
2x+17
Step-by-step explanation:
-4y+8-3x+4y+9+5x
Combine like terms
-3x +5x -4y +4y +8+9
2x +0 +17
Add the polynomials together:
(5x-2)+(2x-3)+(4x+3)
Combine like terms:
(5x+2x+4x) + (-2+-3+3) = 11x-2
So the answer is D.
Answer:
Third option. 
Step-by-step explanation:
For this exercise you need to remember one of the properties for exponents.
There is a property called the "Negative property of exponents" which states the following:
Where 
As you can observe,
is the reciprocal of 
In this case you have the following expression given in the exercise:

Observe the expression. As you can notice, the base "n" has a negative exponent, which is -6.
Therefore, applying the Negative property of exponents explained at the beginning of this explanation, you can simplify the expression.
Then, the simplified form of
is the one shown below:

Answer:
21.6 km/hr
Step-by-step explanation:
multply the speed value by 3.6