To determine the most common injury cared for in any emergency room, a 1 point
reporter goes to the same hospital every afternoon for one month during
the summer and observes people entering the emergency room. She
concludes that second degree sunburn is the most common injury. *

Biased -- Convenience
Biased - Voluntary Response
Unbiased -- Simple Random
Unbiased -- Systematic Random

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".

-6 is the correct option from the above given options