Escitalopram is an oral drug that is used for treating depression and generalized anxiety disorder. Chemically, escitalopram is similar to citalopram . Both are in a class of drugs called selective serotonin reuptake inhibitors (SSRIs), a class that also includes fluoxetine , paroxetine and sertraline .
1 A circle is all of the points that are a fixed distance, known as the radius, from a given point, known as the center of the circle. 2  Explore the standard equation of a circle using the applet below (Go here for a larger version).
1 When the center is at origin and radius is r, the equation of the circle in standard form is given by x2 + y2 = r2. 2  When the radius of a circle is 0, the equation of the circle in standard form becomes (x-h) 2 + (y-k) 2 = 0. 3  This can happen only when the circle reduces to a point.e know that the standard form of a circle is (x-h) 2 + (y-k) 2 = r 2. Comparing the given equation with the standard form, we get. h = -10, k = 4 and r 2 = 25. Taking square root on both sides of r 2 = 25, we get r = 5.