Question

There are 7 books on the floor. The number of books on the shelf is 2 more than 3 times the number of books on the floor. How many books are on the shelf? Enter your answer in the box.

Answer 1

*7 books on the floor *2 more than 3 times the number of books on the floor in the shelf

7x3=21
21+2=23

Answer: There is 23 books on the shelf

Answer 2

For this case, the first thing we must do is define variables.

We have then:

x: the number of books on the floor

y: The number of books on the shelf

We now write the equation that models the problem:

The number of books on the shelf is 2 more than 3 times the number of books on the floor:

`y = 3x + 2`

Then, we evaluate the expression for x = 7.

We have then:

`y = 3 (7) +2`

`y = 21 + 2`

`y = 23`

Answer:

The number of books on the shelf is 23.