Adrianna wants to prove that a given quadrilateral is also a parallelogram. Which approach CANNOT be used to justify her proof? A) Show that both pairs of opposite angles are congruent.
B) Show that both pairs of opposite sides are congruent.
C) Show that the diagonals are congruent.
D) Show that all pairs of consecutive angles are supplementary.

What is the length of the segment, endpoints of which are intersections of parabolas y=x2? 11 4 x? 7 4 and y=? 7 8 x2+x+ 31 8 ?

Solve for x: 5/3 x = 20/21 it's fraction. remember to simplify your fraction

Statements reasons 1. ab ? cd; ad ? bc 1. given 2. ac ? ac 2. reflexive property 3. ? adc ? ? cba 3. ? 4. ? dac ? ? bca; ? acd ? ? cab 4. cpctc 5. ? dac and ? bca are alt. int. ? s; ? acd and ? cab are alt. int. ? s 5. definition of alternate interior angles 6. ab ? cd; ad ? bc 6. converse of the alternate interior angles theorem 7. abcd is a parallelogram 7. definition of parallelogram what is the missing reason in step 3?