Help me please also whoever solves it correct ill mark him brainlist

Determine the area of a triangle with (see picture below)

Kelli swam upstream for some distance in a hour. she then swam downstream the same river for the same distance in only 6 minutes. if the river flows at 5km/hr, how fast can kelli swim in still water?

Graph each quadratic function and identify its key characteristics. f(x) = x^2 - 2x - 3