Final answer:
According to the U.S. Constitution, if the two houses of Congress cannot agree on adjournment, neither house can unilaterally adjourn without the consent of the other house.
Step-by-step explanation:
According to the U.S. Constitution, if the two houses of Congress cannot agree on adjournment, neither house can unilaterally adjourn for more than three days or to any other place without the consent of the other house. This means that if there is a disagreement, both houses need to come to a mutual agreement on the timing of adjournment.