Answer:
In step 5, andrew made a mistake by subtracting 9.8 instead of adding 9.8. Andrew should've have obtained the answer -2, but because of his mistake the answer is incorrect.
Answer:

Step-by-step explanation:
GIVEN: A farmer has
of fencing to construct a rectangular pen up against the straight side of a barn, using the barn for one side of the pen. The length of the barn is
.
TO FIND: Determine the dimensions of the rectangle of maximum area that can be enclosed under these conditions.
SOLUTION:
Let the length of rectangle be
and
perimeter of rectangular pen 


area of rectangular pen 

putting value of 


to maximize 



but the dimensions must be lesser or equal to than that of barn.
therefore maximum length rectangular pen 
width of rectangular pen 
Maximum area of rectangular pen 
Hence maximum area of rectangular pen is
and dimensions are 
Answer:
4x^2-6x-8
Step-by-step explanation:
For this case we have the following expression:
414x - 812y - 414x
Rewriting we have:
414x - 414x - 812y
We group similar terms:
(414x - 414x) - 812y
Adding we have:
0 - 812y
- 812y
Answer:
The sum of a number and its opposite is 0, and the sum of any number and 0 is the number itself.
12.) First find the rate of miles/hour that the Morales family drove: 312 miles/6 hours = 52 miles/hour. To find how far they travel in 8 hours, multiply that rate by 8. 52 x 8 = 416. If they drive for 8 hours, they will travel 416 miles.