Add and subtract integers

Zero Pair A pair of integer chips, with one chip representing +1 and one chip representing -1 + 1 - 1 The pair represents zero because ( + 1 ) + ( - 1 ) = 0

Sum of any two opposite integers is zero Two integers with same numeral, but different signs. For example. + 2 - 2 Two integers represented by points that are the same distance in opposite direction from zero on a number line. Sum of any two opposite integers is zero

Writing and reading Integer Sums The + or – sign of an integer does not represent addition or subtraction. To avoid confusion, use brackets to distinguish integer signs from operation symbols. For example, write (+2) + (-2), not +2 + -2. You may find it helpful to read (+2) + (-2) as “positive two plus negative two”

What addition statement does each represent?

Solve (+3) + (+4) = (-2) + (-4) = (+5) + (-2) = (-8) + (+8) = (+3) + (+4) = (-2) + (-4) = (+5) + (-2) = (-8) + (+8) = (-4) + (-1) = (+2) + (+6) = (-7) + (+4) = (+8) + (-3) = (+2) + (+3) = (+3) + (+2) = (-1) + (-4) = (-4) + (-1) = (+2) + (-2) = (-2) + (+2) =

Sample Integer Problem Raphy spend $5 on bus fares to visit his aunt. During the visit, she gave Raphy $12 for doing some yard work. How much money did Raphy gain from visit?

Solution Represent the $5 Raphy spent by a negative integer, -5 Solution Represent the $5 Raphy spent by a negative integer, -5. Represent the $12 Raphy received by a positive integer, +12. The money that Raphy gained from the visit can be represented by the sum (-5) + (+12). Add (-5) + (+12) using integer chips. (-5) + (+12) = + 7 “Raphy gained $7 from the visit”

Use the sum of two integers to represent each situation Jane found $10 and then lost $4. How much did she have left? A Snail slid 7 cm down a stalk and climbed 5 cm back up. How far was the snail below its original position? In one game, the Rockies girls soccer team scored 4 goals and had 1 goal scored against it. How many goals did the team win by? A Scuba diver dove 4 m under the water and then went down another 8 m. What was the diver’s final depth under the water.

Use integer addition to determine your answer Jamal spend $6 on Saturday morning and another $9 on Saturday afternoon. How much less money did he have at the end of the day than at the beginning? The temperature on the Mosse Lake Reserve in Manitoba was +60 C. The temperature dropped by 100 C to reach the overnight temperature. What was the overnight low temperature?

Use the sum of two integer to represent each situation What was sum? Explain the meaning of each numerical answer. Kris had 6 world-music CDs and then bought another 2 world-music CD’s. The temperature went down by 50 C and then up went up by 80 C. Miguel took 4 steps forward and 4 steps backward. Yuan caught 6 fish in his net, but 2 got away as he pulled the net in.

Solve problems and show your work using chips and number line Marc gave Marie 5 roses, 3 roses died. How many roses are left? Pusheen ate 6 slices of pizza, then she bought 12 slices of pizza. Hoe many slices of pizza did she have? The Narwhal dove 7 m into the sea then dove another 7 m. How deep did Narwhal swim? Mr. Singh planted 13 tulips in his garden but 8 of them died. How many tulips left? Mr. Pickle ate 10 pickle and barfed out 10 pickle. How many pickle are left in his stomach?

Solve problems and show your work using chips and number line Ally had 15 inches of hair and she cut 7 inches off. How much hair does she have left? A Unicorn bought 17 pcs of candy and ate 3 pcs. How many candy he left? Jerry spend 6 hours on his project and another 4 hour to proofread. How many hours did it take for him to finish his project? Ben grew 3 inches from May to July and then he grew another inch in August. How much taller did he get? A Shark dove 15 meters in the ocean and swam 6 meters back up. How many meter was he away frim where he started?