\[\begin{array}{ll}{A=c^{2}+4\left(\frac{1}{2} a b\right)} & \color {Red} {\text { Adding the area of the interior square and the area of four right triangles. }} \\ {A=c^{2}+2 a b} & \color {Red} {\t...A=c2+4(12ab) Adding the area of the interior square and the area of four right triangles. A=c2+2ab Simplify: 4((1/2)ab)=2ab
