정수와 유리수

In the morning, the temperature in Anchorage, Alaska was $\text{15 degrees Fahrenheit.}$ By mid-afternoon the temperature had dropped to $30 degrees$ below zero. What was the difference between the morning and afternoon temperatures?

The temperature in Denver was $-6$ degrees Fahrenheit at lunchtime. By sunset the temperature had dropped to $\text{−15 degree Fahrenheit.}$ What was the difference between the lunchtime and sunset temperatures?

Dinesh hiked from Mt. Whitney, the highest point in California, to Death Valley, the lowest point. The elevation of Mt. Whitney is $14,497$ feet above sea level and the elevation of Death Valley is $282$ feet below sea level. What is the difference in elevation between Mt. Whitney and Death Valley?

One day, John hiked to the $10,023 foot$ summit of Haleakala volcano in Hawaii. The next day, while scuba diving, he dove to a cave $80 feet$ below sea level. What is the difference between the elevation of the summit of Haleakala and the depth of the cave?

The submarine Nautilus is at $340 feet$ below the surface of the water and the submarine Explorer is $573 feet$ below the surface of the water. What is the difference in the position of the Nautilus and the Explorer?

Leslie has $\char36 25$ in her checking account and she writes a check for $\char36 8.$

• ⓐ What is the balance after she writes the check?
• ⓑ She writes a second check for $\char36 20.$ What is the new balance after this check?
• ⓒ Leslie’s friend told her that she had lost a check for $\char36 10$ that Leslie had given her with her birthday card. What is the balance in Leslie’s checking account now?

Araceli has $\char36 75$ in her checking account and writes a check for $\char36 27.$

• ⓐ What is the balance after she writes the check?
• ⓑ She writes a second check for $\char36 50.$ What is the new balance?
• ⓒ The check for $\char36 20$ that she sent a charity was never cashed. What is the balance in Araceli’s checking account now?

Genevieve’s bank account was overdrawn and the balance is $-\char36 78.$

• ⓐ She deposits a check for $\char36 24$ that she earned babysitting. What is the new balance?
• ⓑ She deposits another check for $\char36 49.$ Is she out of debt yet? What is her new balance?

Model Subtraction of Integers

In the following exercises, model each expression and simplify.

$8-2$

Model Subtraction of Integers

In the following exercises, model each expression and simplify.

$9-3$

Model Subtraction of Integers

In the following exercises, model each expression and simplify.

$-5-(-1)$

Model Subtraction of Integers

In the following exercises, model each expression and simplify.

$-6-(-4)$

Model Subtraction of Integers

In the following exercises, model each expression and simplify.

$-5-4$

Model Subtraction of Integers

In the following exercises, model each expression and simplify.

$-7-2$

Model Subtraction of Integers

In the following exercises, model each expression and simplify.

$8-(-4)$

Model Subtraction of Integers

In the following exercises, model each expression and simplify.

$7-(-3)$

Simplify Expressions with Integers

In the following exercises, simplify each expression.

• ⓐ $\,15-6\quad$
• ⓑ $\,15+(-6)$

Simplify Expressions with Integers

In the following exercises, simplify each expression.

• ⓐ $\,12-9\quad$
• ⓑ $\,12+(-9)$

Simplify Expressions with Integers

In the following exercises, simplify each expression.

• ⓐ $\,44-28\quad$
• ⓑ $\,44+(-28)$

Simplify Expressions with Integers

In the following exercises, simplify each expression.

• ⓐ $\,35-16\quad$
• ⓑ $35+(-16)$