Question 342987
First, simplify the equations
{{{x^2 + y^2 + 7x - y - 12 = 0}}}
{{{x^2 + y^2 + 6x + 3y - 4 = 0}}}
Subtract the equations from each other to get
a linear dependency between x and y.

Solve it relatively to x or y and substitute to
the one of the original equations.

Solve the resulting square equation.
The rest of the solution is left to the
exercise of the reader.