B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B
Answer:
It takes them 1.875 hours.
Step-by-step explanation:
Here, the job is cleaning the house.
Mom does 1 job in 3 hours.
In 1 hour, mom does 1/3 of the job.
Dad does 1 job in 5 hours.
In 1 hour, dad does 1/5 of the job.
Mom and dad working together do the job in x hours.
In 1 hour, mom and dad together do 1/x of the job.
1/3 + 1/5 = 1/x
5/15 + 3/15 = 1/x
8/15 = 1/x
8x = 15
x = 15/8 = 1.875
Answer: It takes them 1.875 hours.
Answer: Choice D. y = (x-1)^2 - 3
The vertex is (h,k) = (1,-3). So h = 1 and k = -3.
We have a = 1 as the leading coefficient.
Plug those values into the equation below
y = a(x-h)^2 + k
y = 1(x - 1)^2 + (-3)
y = (x - 1)^2 - 3
Check the picture below.
so we know the radius of the semicircle is 2 and the rectangle below it is really a 4x4 square, so let's just get their separate areas and add them up.
![\stackrel{\textit{area of the semicircle}}{\cfrac{1}{2}\pi r^2}\implies \cfrac{1}{2}(\stackrel{\pi }{3.14})(2)^2\implies 3.14\cdot 2\implies 6.28 \\\\\\ \stackrel{\textit{area of the square}}{(4)(4)}\implies 16 \\\\[-0.35em] ~\dotfill\\\\ ~\hfill \stackrel{\textit{sum of both areas}}{16+6.28=22.28}~\hfill](https://tex.z-dn.net/?f=%5Cstackrel%7B%5Ctextit%7Barea%20of%20the%20semicircle%7D%7D%7B%5Ccfrac%7B1%7D%7B2%7D%5Cpi%20r%5E2%7D%5Cimplies%20%5Ccfrac%7B1%7D%7B2%7D%28%5Cstackrel%7B%5Cpi%20%7D%7B3.14%7D%29%282%29%5E2%5Cimplies%203.14%5Ccdot%202%5Cimplies%206.28%20%5C%5C%5C%5C%5C%5C%20%5Cstackrel%7B%5Ctextit%7Barea%20of%20the%20square%7D%7D%7B%284%29%284%29%7D%5Cimplies%2016%20%5C%5C%5C%5C%5B-0.35em%5D%20~%5Cdotfill%5C%5C%5C%5C%20~%5Chfill%20%5Cstackrel%7B%5Ctextit%7Bsum%20of%20both%20areas%7D%7D%7B16%2B6.28%3D22.28%7D~%5Chfill)
First multiply 40 and 10 to get 400. Then multiply 400 by 8 to get 3,200.
Your answer would be: 3,200
