Important Concepts
What is absolute value?
The distance of a number is from zero.
(Distance can't be negative)
Solve:
-5 + 9
4
-4 - 6
-4 + (-6) = -10
Timothy dives 10 feet under water and swims back up 3 feet. Where is his current location in the water?
-10 + 3= -7
7 feet below the surface
What are integers?
All positive and negative whole numbers and 0.
Solve:
-12 + 5
-7
4 - 11
4 + (-11) = -7
Janiah gets paid $100, and then must pay her cable bill which is $245. What is the balance of her bank account?
100 - 245 = $-145
Solve:
-16 + (-17) + 15
-18
115 - (-77)
115 + 77 = 192
The temperature this morning is now 54 degrees, it rose 12 degrees overnight. What temperature was it last night?
54-12 = 42 degrees
What does this mean? |-6| = 6
The absolute value of -6 is 6, or -6 is 6 units from zero.
How do you find the sum of numbers with different signs?
Subtract the numbers and take the sign of the # with the greater absolute value.
-27 - (-33) - 5
-27 + 33 - 5 = 1
In a game, TK earned 15 points in the first round, in the 2nd round he lost 20 points for not showing good sportsmanship. In the final round, he scored double what he did in the first round. What is his final score?
15 + (-20) + 30 = 25 points
Subtracting a positive number is the same thing as...
Adding its negative...
Example: 7-4 = 7 +-4
Solve:
-16+ -188+ -17.5
-221.5
-10 - 11 - (-3)
-10 + (-11) + (3)= -18
Neveah starts with $1,000 in her bank account, she withdraws $750 to pay her rent. Then, she lets a friend borrow $70, and buys new clothes for $120. She finds $100 cash on the street, and deposits 1/4 of it. How much money is in her bank account?
$85