Posted by karla on Tuesday, January 18, 2011 at 9:45pm.
y^2-3y=9 y^2 - 3y = 9 complete the square y^2 - 3y + 9/4 = 9 + 9/4 (y - 3/2)^2 = 45/4 +- (y - 3/2) = 45/4 solve for y y = 3/2 (sqrt5 + 1) y = -3/2 (-1 + sqrt5)