Is 16 and 40 relatively prime?

No

Step-by-step explanation:

Relatively prime means that the only common factor the 2 numbers share is 1

factors of 16 are 1, 2, 4, 8, 16

factors of 40 are 1, 2, 4, 5, 8, 10, 20, 40

common factors are 1, 2, 4, 8

Hence 16 and 40 are not relatively prime

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".

y=1/4x-4

step-by-step explanation: