Solve the simultaneous equation:

Question

x^2 + y^2 = 13 and x + 3y = -3

Answer 1

x = -3 (y + 1)

x^2 = 9 (y^2 + 2y + 1)

substitute and solve for y

there will probably be two solutions
... the intersection(s) of a circle and a line

Answer 2

x^2 + y^2 = 13 and x + 3y = -3