Page 22 - Math Course 1 (Book 1)

Adding Integers

REAL WORLD EXAMPLE

Solve the Equation.
WEATHER -22 + 19 = x To f nd the sum, subtract
| 19 | from | -22 |.

On February 1, the - 3 = x The sum is negative
temperature at dawn because | -22 | > | 19 |.
was –22°F. By noon,
it had risen 19
degrees. What was the The temperature at noon
temperature at noon? Answer was -30 F.

Words: The temperature at dawn was –22°F.
It had risen 19 degrees by noon. Add Integers with the
What was the temperature at noon? Same Sign
Variable: Let x = the temperature at noon.
Find –5 + (–4).

Equation: –5 + (–4) = –9 Add |–5| and |–4|. Both

Temperature plus increase equals Temperature numbers are negative,
so the sum is negative.
at dawn by noon at noon

-22 + 19 = x
Answer -9

Your Turn! FOOTBALL

Add Integers on a Number Line Dave started his hike at
32 feet below sea level.
Find -2 + 5 During the hike he gained
A. 7 B. -7 C. 3 D. -3 an altitude of 29 feet. At
what altitude did Dave
Answer complete his hike?

A. 3 feet above sea level
B. 3 feet below sea level
C. 61 feet above sea level
D. 61 feet below sea level

Add Integers with the Same Sign Answer

Find -3 + -8
A. 5 B. -5 C. 11 D. -11

Answer

14