Each (1/3) shift would be 20 min. There are 3 shifts every hour and there are 3hrs.
3x3= 9 shifts
Answer:
D. (-10, -3), (-3, -10)
Step-by-step explanation:
For a question like this, it is easiest to check the offered answers in the given equations.
The first equation requires the sum of the x- and y-values to be -13. Adding two numbers is pretty easy, so you can rapidly determine that choice D is the only reasonable choice.
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<em>Comment on the process</em>
Answering multiple-choice questions is as much about test-taking skill as it is about math skill. First, you eliminate choices that don't answer the question.
Then you see if there is a way to identify the "correct" answer from the remaining "reasonable" answers. Often, that requires you only solve part of the problem, or you check for consistency between parts of the answer. (Here, if (a, b) is an answer, then (b, a) will be the other answer. Again, only choice D has that characteristic.)
You can see if the answer choices satisfy the details of the problem requirements.
Finally, <em>as a last resort</em>, you actually work the problem to determine your own answer to the question. (Here, you can substitute for y: x^2 +(-13-x)^2 = 109, then solve the quadratic, 2x^2 +26x +60 = 0 to find x=-3 or -10.) When you're done with this, you also need to <em>check your answer</em> against the above criteria.
Answer:
,
etc.
Step-by-step explanation:
Multiply the top and bottom of 
by the same number to get an equivalent fraction.
We are given
number of heads =15
we know that
any healthy dragon has three heads
horse has 1 head
chicken has 1 head
Let's assume
number of dragons is x
number of horses is y
number of chickens is z
so, we will get
first equation:
number of legs =50
any healthy dragon has four legs
chicken has 2 legs
horse has four legs
so, we can get second equation as
we can simplify it
now, we can find third equation
dragon has two wings
horse has no wings
chicken has two wings
so, we will get third equations as
now, we can simplify it
so, we will get system of equations as
now, we can use substitution
We can find for z from third equation
we can plug this in first equation
now, we can solve for y
now, we can plug this z and y into second equation
now, we can solve for x
now, we can find y and z
we can plug x=1
we can plug x=1
Hence ,
number of dragons is 1
number of horses is 11
number of chicken is 1............Answer
