The answer is that y is equal to -3 and x is equal to 7
2x-y=17
-2(x-y)=10 )
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2x-y=17
-2x+2y=-20
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y=-3
x-y=10
x-(-3)=10
x+3=10
-3 -3
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x=7
Estimation:
23 --> rounded to 20
71 --> rounded to 70
70 + 20 = 90. I rounded both numbers down so the exact sum must be only a little greater than my estimate.
First do 12-5, which equals 7. Next, subtract 1/10 from 2/5. 2/5 is the same as 4/10 if you multiply both the numerator and denominator by 2. 4/10-1/10=3/10. Now add 7 and 3/10. You will get 7 3/10 as the answer, which is letter C.)
Answer:
D. The work shown above is correct, and ![y^5\sqrt[4]{y^3}](https://tex.z-dn.net/?f=y%5E5%5Csqrt%5B4%5D%7By%5E3%7D)
may not be simplified further.
Step-by-step explanation:
If you add all the exponents of y in first line then we get
4+4+4+4+4+3=23
Which is same as the exponent in original problem.
So first line is good.
Since it is 4th root so each 
will turn into y when it moves out of the radical so final answer is correct.
Hence correct choice is "D. The work shown above is correct, and may not be simplified further." is the correct answer.
