Could someone help, please?

DCB=33

Step-by-step explanation:

We are given the angle for a and we know the angle for ADC is 90 because AB & DC are perpendicular.  Given two angles of a triangle we can find the third by subtracting the two known values from 180 because we know a triangle totals 180.

180-33-90=57

So we can also find CDB because we know AB & DC are perpendicular.  It is also 90 because two perpendicular lines make a 90 angle.  

DCB can be found because we know that ACB makes a 90 angle and the ACD portion is 57.  So we subtract 57 from 90.

90-57=33

We can also find CBD by subtracting CDB and DCB from 180.

180-90-33=57

More than question asked but wanted to help you see connections between them.

answer: a.

step-by-step explanation: the answer is a. because, you need to converge the fractions to find a solution.