Answer:
See explanation
Step-by-step explanation:
In quadrilateral BADC,
AB= AD
BC= DC
AC is a line of symmetry for this quadrilateral
Consider triangles BAC and DAC. In these triangles,
- AB = AD - given
- BC = DC - given
- AC = AC - reflexive property
So, ΔBAC ≅ ΔDAC by SSS postulate.
Congruent triangles have congruent corresponding sides and angles, so
m∠ACB = m∠ACD
<u>Another way:</u> The line of symmetry can be defined as the line that divides the figure into two identical figures. Thus, ΔBAC and ΔDAC are identical (congruent) and have congruent corresponding sides and angles.
