I believe it was a rectangle I'm not sure test it out.
Answer:
The cost of hardbook is $9 and cost of paperback is $5.
Step-by-step explanation:
Let x be the price for hardback book and y be the price for paperback book.
Mr. Yamamoto purchased 42 new hardcover books and 64 new paperback books, which cost a total of $698.
We can write the equation as:

He also purchased 42 new hardcover books and 58 new paperback books, which cost a total of $668.
We can write the equation as:

We have to use the elimination method to solve the two equations.
We eliminate x by subtracting the two equations.

Thus, the cost of hardbook is $9 and cost of paperback is $5.
Answer:
-2y+6
Step-by-step explanation:
Multiply (y-3) by -2