Hey, i'm dumb and need . prove that opposite sides of a parallelogram are congruent. be sure to create and name the appropriate geometric figures. (10 points) (the blanks below need to be filled in) let abcd be a parallelogram. by definition of a side ab is parallel to side cd and side bc is parallel to side da. construct diagonal bd using a straightedge. ∡abd is congruent to ∡bdc by thetheorem. by the same theorem, ∡cbd is congruent to ∡adb. segment bd is congruent to itself by the property of equality. therefore, abd is congruent to cdb by and opposite sides of parallelogram abcd are congruent by ye kindly.