### 2.1 Solving Problems by Creating an Equation

```2.1
Solving Problems by Creating an
Equation
Solving a Problem by Creating an
Equation
Toucans and blue-and-yellow macaws are both
tropical birds. The length of an average toucan
is about two thirds of the length of an average
blue-and-yellow macaw. Toucans are about 24
in. long. What is the length of an average blueand-yellow macaw?
Solving a Problem by Creating an
Equation
Toucans and blue-and-yellow macaws are both
tropical birds. The length of an average toucan
is about two thirds of the length of an average
blue-and-yellow macaw. Toucans are about 24
in. long. What is the length of an average blueand-yellow macaw?
x = I don’t know the length of a macaw
I do know toucans are 24 in long
I do know toucans are 2/3 as long as macaws
Solving a Problem by Creating an
Equation
Toucans and blue-and-yellow macaws are both tropical birds. The length of
an average toucan is about two thirds of the length of an average blue-andyellow macaw. Toucans are about 24 in. long. What is the length of an
average blue-and-yellow macaw?
x = I don’t know the length of a macaw
I do know toucans are 24 in long
I do know toucans are 2/3 as long as macaws
X=2
3
x
Solving a Problem by Creating an
Equation
An online DVD rental company offers gift
certificates that you can use to purchase rental
plans. You have a gift certificate for \$30. The
plan you select costs \$5 per month. How many
months can you purchase with the gift
certificate?
Solving a Problem by Creating an
Equation
An online DVD rental company offers gift
certificates that you can use to purchase rental
plans. You have a gift certificate for \$30. The plan
you select costs \$5 per month. How many months
can you purchase with the gift certificate?
x = I don’t know how many months I can buy with
the certificate
I do know I have \$30
I do know each month costs \$5
Solving a Problem by Creating an
Equation
An online DVD rental company offers gift certificates that you can use to
purchase rental plans. You have a gift certificate for \$30. The plan you select
costs \$5 per month. How many months can you purchase with the gift
certificate?
x = I don’t know how many months I can buy with
the certificate
I do know I have \$30
I do know each month costs \$5
30 = 5x
Solving a Problem by Creating an
Equation
are one third of the way through the book.
Write and solve an equation to find the number
of pages in the book.
Solving a Problem by Creating an
Equation
are one third of the way through the book.
Write and solve an equation to find the number
of pages in the book.
x = I don’t know how many pages are in the
whole book
I do know I am finished with 1/3 of the book
Solving a Problem by Creating an
Equation
You have already read 117 pages of a book. You are one third of the way
through the book. Write and solve an equation to find the number of pages
in the book.
x = I don’t know how many pages are in the
whole book