Answer:
See explanation
Step-by-step explanation:
a) To prove that DEFG is a rhombus, it is sufficient to prove that:
- All the sides of the rhombus are congruent:

- The diagonals are perpendicular
Using the distance formula; 








Using the slope formula; 
The slope of EG is 

The slope of EG is undefined hence it is a vertical line.
The slope of DF is 

The slope of DF is zero, hence it is a horizontal line.
A horizontal line meets a vertical line at 90 degrees.
Conclusion:
Since
and
, DEFG is a rhombus
b) Using the slope formula:
The slope of DE is 

The slope of FG is 

Answer:
$17.21
Step-by-step explanation:
Just line up the decimals and then you add. But after you finished adding, make sure you just straight up bring the decimal down to your final answer to the question.
11.00*9.5=104.5
104.5*0.07=7.315
7.315+104.5=111.815
2/3+1/3x=2x
2+1x=6x
x-6x=-2
-5x=-2
x=2/5