Worth 20 points Il will mark brainiest! :) The picture is included too oh and the question is already in the picutre but just incase you cant see what it says it says this

In the diagram below lines, AB and CD are . sorry if the picture is a bit dark

A. Perpendicular!

Because they cross with a 90 degree angle :]

he used the algebra tiles correctly.

step-by-step explanation:

given : 3x(2x-1)

solution :

since he used algebra tiles .

armando's solution is the same in the solution shown in figure

as he distributed 2x into x and x and wrote them vertically

and also write   -1 vertically

and 3x into x and x and x and wrote it horizontally

performing the multiplication in the algebra tiles we get

and solving the given expression :

3x(2x-1)

since solving the expression using tiles   and solving the expression algebraically we get the same answer

thus   we can choose the first statement as the answer to this problem which is "he used the algebra tiles correctly".

hello! just here for points! though i wish i knew!