4. Deep-sea divers Jacques Cousteau and his assistant are searching for sunken
treasure. Jacques Cousteau is currently
13.9 meters below the surface (-13.9
meters) and his assistant is currently 97.3
meters below the surface (-97.3 meters).
Jacques Cousteau is swimming down at
the rate of 7.5 meters per minute, and his
assistant is swimming towards the surface
at 6.4 meters per minute.
3
a. What is the depth of each diver
3 minutes from now?
b. In how many minutes will the assistant
be 33.3 meters below the surface?
c. According to the algebraic model, in
how many minutes will the divers be at
the same depth?

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".