Anonymous

x^2 - 2y^2 = 23 x - 2y = 7 x = 2y + 7 (2y + 7)^2 - 2y^2 = 23 2y^2 + 28y + 26 = 0 2(y^2 + 14y + 13) = 0 2[y(y + 13) + (y + 13) = 0 2(y + 13)(y + 1) = 0 Solutions: x = 5, y = -1 x = -19, y = -13

Anonymous

(7+2y)^2-2y^2 = 23 49+28y+2y^2 = 23 2y^2+28y+26 = 0 y^2+14y+13 = 0 (y+13)(y+1) = 0 y = -1 or -13 x = 5 or -19 Answer x = -19 & y = -13 or x = 5 & y = -1

Anonymous

http://www.wolframalpha.com/input/?i=x%5... Solve for the easier one on bottom. Substitute it for the harder one on top. The solve the one on top. You should get at least one solution that way.

Anonymous

x^2 - 2y^2 = 23 x - 2y = 7 (2y + 7)^2 - 2y^2 = 23 2y^2 + 28y + 26 = 0 2(y^2 + 14y + 13) = 0 2(y^2 + 13y + y + 13) = 0 2[y(y + 13) + (y + 13) = 0 2(y + 13)(y + 1) = 0 Solutions: x = -19, y = -13 x = 5, y = -1