Answer:
Step-by-step explanation:
Notice that in the second equation, the coefficient of 
is 
times greater than in the first. Therefore, by making the coefficient of 
in the second equation times greater than in the first, it's impossible to only isolate one variable.
Therefore, when 
, there are no solutions to this system.
Answer:
D. Only one cleaning product was asked about in the survey.
Any given company can use more than one cleaning product or even use a combination of different cleaning products. The question was not specific enough, since it should have probably asked which cleaning products are used and which ones are used more frequently.
Step-by-step explanation:
the other options are wrong because:
- A. Only 50 cleaning services were surveyed. ⇒ This actually would increase the validity of the claim because it satisfies the the condition for a valid confidence interval [np and n(1 - p) are larger than 10]-
- B. Cleaning services were selected at random. ⇒ This actually would increase the validity of the claim.
- C. A well-known company conducted the survey. ⇒ This actually would increase the validity of the claim.
Second option because they they should have put the +1
Answer:
Step-by-step explanation:
Begin by squaring both sides to get rid of the radical. Doing that gives you:
Now use the Pythagorean identity that says
and make the replacement:
. Now move everything over to one side of the equals sign and set it equal to 0 so you can factor:
and then simplify to
Factor out the common cos(x) to get
and there you have your 2 trig equations:
cos(x) = 0 and 1 - cos(x) = 0
The first one is easy enough to solve. Look on the unit circle and see where, one time around, where the cos of an angle is equal to 0. That occurs at
The second equation simplifies to
cos(x) = 1
Again, look to the unit circle and find where the cos of an angle is equal to 1. That occurs at π only.
So, in the end, your 3 solutions are
