Domain means the values that can be used as a function's input. Since all real values of x will yield a real value of f(x), the domain is (-infinity, infinity).
Answer:
56
Step-by-step explanation:
Basically you want to find out what is 70% of 80.
first you have to set up your problem
= 
the first fraction would be the percent (70) over 100. (you always use 100)
The fraction to the left would be n over 80. the denominator (the number on the bottom) would be the whole amount. n would be the unknown number
To solve you would use the butterfly method. 80 x 70 and 100 x n. 80 x 70 is 5600 and 100 x n is 100n.
The final step is dividing. 5600 divided by 100 giving you 56
2x+3x+x+9 = ??
5x+x+9 = ??
6x+9= ??
6x = -9 ---- subtract 9 on both sides
x = - 3/2 ----- didvide by 6 on both sides, simplify
The cheaper option is Best Buy where the TV would close $455 compared to Micro Center which out be $480.
Ann wants to choose from two telephone plans. Plan A involves a fixed charge of $10 per month and call charges at $0.10 per minute. Plan B involves a fixed charge of $15 per month and call charges at $0.08 per minute.
Plan A $10 + .10/minute
Plan B $15 + .08/minute
If 250 minutes are used:
Plan A: $10+$25=$35
Plan B: $15+$20=$35
If 400 minutes are used:
Plan A: $10+$40=$50
Plan B: $15+$32=$47
B is the correct answer. How to test it:
Plan A: $10+(.10*249 minutes)
$10+$24.9=$34.9
Plan B: $15+(.08*249 minutes)
$15+$19.92=$34.92
Plan A < Plan B if less than 250 minutes are used.