Decisively the system of equations, adding and subtracting its equations: 11x-7y = 0 13x-7y = 8.

Solution of the system by term-by-term subtraction.
1. From the 1st equation of the system, subtract the 2nd:
11 x – 7 y – 13 x – (-7 y) = 0 – 8,
-2 x = -8,
x = -8: (- 2),
x = 4.
2. Determine the value of y:
11 x – 7 y = 0,
11 4 = 7 y,
y = 44: 7,
y = 6 2/7.
3. Verification:
11 4 – 7 44/7 = 44 – 44 = 0,
13 4 – 7 44/7 = 52 – 44 = 8.
Answer: x = 4, y = 6 2/7.