The proof shows that ABCD is a rhombus. Which of the following is the
missing reason?
Prove: ABCD is a rhombus
Statements
1. ABCD is a parallelogram and
AD= AB.
AB a DC, AD a BC
2.
3.
AB a CD a AD a BC
4. ABCD is a rhombus.
Reasons
1. Given
PREVIOUS
2. ?
3. Transitive property
4. By definition, if all four sides of a
parallelogram are congruent, then
it is a rhombus.
QED
O A. Consecutive sides of a parallelogram are parallel.
B. Opposite sides of a parallelogram are parallel.
C. Opposite sides of a parallelogram are congruent.
O D. Consecutive sides of a parallelogram are congruent.