Answer: I think its $176.40
Step-by-step explanation:
The area would be 21
Feet would be = 50.4 (21 x 2.4)
Then it would cost $176.40 (50.4 x $3.50)
I might be wrong, I'm not entirely sure.
To solve this do:
838.35/9315= 0.09.
This means the company charged $.09 for every kilowatt of electricity used.
Answer:
1. I have simplified the first question:

2. I have found the parabola properties:

So basically you just need to do the Pythagorean theorem to find the sides of the shaded rectangle, with c being the length of the side.
Small side:
2^2 + 6^2 = c^2
4 + 36 = c^2
40 = c^2
C is similar to 6.32456
Long side:
12^2 + 4^2 = c^2
144 + 16 = c^2
160=c^2
C is similar to 12.64911
And then you just multiply!