Answer:
(x, y) = (0, -1)
Explanation:
Since we have an expression for y, it is convenient to substitute that into the second equation:
4x -7(-7x -1) = 7
4x +49x +7 = 7
53x = 0
x = 0
Substituting into the first equation gives ...
y = -7·0 -1
y = -1
The solution is (x, y) = (0, -1).