Ineed the answer to question 8. 50 points up for grabs

Let iron = x

There is 1.5 times the amount of zinc that there is iron, so you get zinc = 1.5x

There is 3 times as much copper as there is zinc, so 1.5 x 3 = 4.5, so copper equals 4.5x

Now all three need to equal the total weight of 210:

X + 1.5x + 4.5x = 210

Simplify:

7x = 210

Divide both sides by 7:

x = 210 /7

x = 30

Now you have a value for x, you can solve for the amount of each material.

Iron = x = 30 g

Zinc = 1.5x = 1.5(30) = 45 g

Copper = 4.5x = 4.5(30) = 135g

There is 45 g of zinc.

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".

i dont know

step-by-step explanation: