All four sides of a rhombus are equal.  AB = 2 in. = BC = CD = DA 

Begin by drawing CD 2 inches long:



With your protractor, carefully measure an angle at C, which is angle BCD 
which is 55°, and draw CB exactly 2 inches long.



The angle at B must be supplementary to the angle at C, which is 55°.
So we subtract 180°-55° = 125°. 

So with your protractor, carefully measure an angle at D, which is angle
ABC = 125°, and draw BA exactly 2 inches long.



Finally draw AD, and you're done:



Edwin