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:
no se podrías resolverlo tu
The answer you are looking for is -11/10 or - 1 1/10.
To find this answer you must first make the denominators the same. To do this, multiply 2/5 by 2/2 to get 4/10. Finally, subtract the two fractions, keeping in mind the denominators stay the same. -7/10 - 4/10 = -11/10 or - 1 1/10.
I hope this helps!