Question 63449
1. Solve the system of equations using the addition (elimination) method.
If the answer is a unique solution, present it as an ordered pair: (x, y). If not, specify whether the answer is “no solution” or “infinitely many solutions.”
1st:  x + 2y = 5
2nd: 3x + 4y = 1 
-------------
Multiply 1st by 2 to get:
3rd: 2x+4y = 10
-----------------
Subtract 3rd from 2nd to get:
4th: x=-9
-------------
Substitute x=-9 into 1st to solve for y, as follows:
-9+2y=5
2y=14
y=7
-------------
Final solution:
x=-9. y=7
--------------

2. Solve the system of equations using the addition (elimination) method.
If the answer is a unique solution, present it as an ordered pair: (x, y). If not, specify whether the answer is “no solution” or “infinitely many solutions.”
1st:  5x – 4y = 1
2nd: -10x + 8y = -3
---------
Multiply 1st by 2 to get:
3rd: 10x-8y=2
----------
Add 3rd to 2nd to get:
0.-1
This is a contradiction and implies there 
is no solution to the system of equations.
-----------
Cheers,
Stan H.