Properties of the Deltoid: Can this be true?

Can a deltoid have only one pair of equal adjacent sides?

No

Is there a deltoid with 3 right angles?

Yes

Is there a deltoid with 4 equal sides?

Yes

Can a deltoid have only one right angle?

Yes

Is there a deltoid that has exactly two right angles?

Yes

Is there a deltoid whose diagonals are not perpendicular?

No

Is there a deltoid whose diagonals do not intersect?

Yes