## Elementary Geometry for College Students (5th Edition)

First of all, we see that point C is $(-5,3)$, for it is C reflected across the y axis. Now, we can find the height and the base of the triangle: $b = 5 - (-5) =10$ $h = 3 - 1 = 2$ Thus: $A = (1/2)(2)(5) = 5$