Answer:
-384x - 120y
Step-by-step explanation:
General Concepts and Formulas:
Brackets
Parentheses
Exponents
Multiplication
Division
Addition
Subtraction
Steps:
1) Distribute

We must distribute the expression above by multiplying -12 by the coefficients and then adding the variables.
So first, multiple -12 by 32 and add the variable 'x' when getting the product:
-12(-384x - 10y)
Now that we have one part, let's solve the other part.
We now must multiple -12 by -10, which gets us 120, now we must plug in:
(-384x - 120y)
(Remove parenthesis)
⇒ -384x - 120y

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So, we have the following equation...

Remember
and
is the following...

Therefore, 
So, your final answer is
.
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Answer:
a) x changes by 6.5 units
b) y changes by 13 units
Step-by-step explanation:
a. Over this interval, how much does x change by?
Initially, we have that x = 2.
In the end, we have that x = 8.5.
So x changes by 8.5-2 = 6.5 units
b. Over this interval, how much does y change by?
Initially, when x = 2, we have that y = 2x + 11 = 2*2 + 11 = 15
In the end, when x = 8.5, we have that y = 2*8.5 + 11 = 28
So y changes by 28 - 15 = 13 units