The derivative gives the slope of the tangent line at any point. simply find the derivative and plug in x = 2 to find the slope at the point on the curve where x is 2. then after finding the corresponding y-coordinate, you can use the point-slope form of a line to find the tangent line. see my response below for directions to where you can get more information

I did a question very similar to this just a while ago. see here. if you don't get it say so...but please try to get it.and then the following question is like to find the equation of the tangent to y=x^2 -2y+5=0 which is perpendicular to the line x-2y+5=0

????? how do u do it wen u hav to hav find it perpendicular to that