Answer:
<h2>PART A: x = 15 and y = -8</h2><h2>PART B: x = -5 and y = 3</h2>
Step-by-step explanation:
PART A:
The first equation is 
The second equation is 
Putting the value of y from (a) in the above equation, we get 
From (a) we get y = 7 - x = 7 - 15 = -8
PART B:
Here the system of equations are 
From (a) we get, 
Putting the above value of x in (b) we get, 
Hence, 
If you're comparing 1.435 * 10^(-3) mm to 1.435 * 10^3 mm, then the more reasonable measurement is 1.435 * 10^3 mm since,
1.435 * 10^3 mm = 1435 mm = 1.435 meters
1 meter is about 3.28 feet approximately
So 1.435 meters is slightly larger (about 4.708 feet) which is a fairly reasonable distance between the tracks on a railroad.
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Something like 1.435 * 10^(-3) mm is equal to 0.001435 mm, which is far less than 1 mm.
81- answer is ok but im not suree
Answer:

Step-by-step explanation:
