This is the concept of geometry, we are required to prove the congruence of the triangles ADC and ABC shown in the figure using the properties that have been stated. SSS (side-side-side) is a property that uses side lengths to prove congruence. In the figure, AD=AB, DC=BC, AC=AC. This indicates that the figure satisfies this property. SAS (side-angle-side) is a property that uses two sides and at least one angle to prove that a set of figures are congruent to each other. Therefore combining the two properties we can mathematically conclude that triangle ADC is congruent to ABC.
