text: circles and triangles? in triangle abc, the coordinates are a(5,0) b(-4,-9) and c(3,3). ab is the diameter of circle f, bc is the diameter of circle g, and ac is the diameter of circle h. find:  a) area of triangle fgh b) area of circle fgh c) area of the region common to circles f, g, and h. let me try it:  a) area of triangle:   a/1) plot a graph. draw a perpendicular from c to ab. area = 1/2 * ab * perpendicular distance.  a.2) area = 1/2 [x1 (y1-y2) + x2 (y2-y3) + x3 (y3-y1)]  where x1, x2, x3 are x - cordinates and y1, y2, y3 are y-cordinates.   a.3) distance between any two points = sqrt |(x^2 - y^2)| using this find ab, bc and ca. area= sqrt (s* (s-ab) * (s-bc) * (s-ca)) where s = (ab+bc+ca) * 0.5  (b) ab is the diameter of circle f. area = pi * (ab^2) * 0.25   (c) this needs to be plotted probably to know their intersection. this can also be done using integral calculus. i am not sure what is your level of proficeincy in calculus.