Integers: Class 7 maths video

0:00 Class 7 maths. Integers.

0:03 Welcome aboard, Hero!

0:05 Captain Calc needs your math superpowers to defeat negative confusion and master integers.

0:11 Adding and Subtracting Integers.

0:14 Integers include zero, positive numbers, and negative numbers.

0:19 When adding integers with the same sign, add their values and keep the common sign.

0:25 Try this one. Find the value of -7 + (-5).

0:31 Both numbers are negative.

0:34 Add their absolute values: 7 + 5 = 12.

0:38 Keep the negative sign: -12.

0:42 So the answer is -12.

0:44 Properties of Addition and Subtraction.

0:48 Integers are closed under addition and subtraction, meaning the result is always an integer.

0:54 Addition is commutative because changing the order of numbers gives the exact same sum.

1:00 Try this one. Verify the commutative property for -6 and 9.

1:07 Add -6 + 9 to get 3.

1:11 Add 9 + (-6) to get 3.

1:14 Both orders give 3, proving addition is commutative.

1:19 So the answer is 3.

1:21 Multiplying Integers.

1:23 The product of two integers with the same sign is always a positive integer.

1:28 The product of two integers with opposite signs is always a negative integer.

1:34 Try this one. Calculate: (-7) × (-8).

1:40 Both factors are negative.

1:42 Multiply absolute values: 7 × 8 = 56.

1:48 Same signs yield a positive product: 56.

1:52 So the answer is 56.

1:54 Dividing Integers.

1:56 Dividing two integers with the same sign gives a positive quotient.

2:01 Dividing two integers with different signs gives a negative quotient.

2:06 Try this one. Calculate: (-72) ÷ 8.

2:13 The signs are different, so the quotient will be negative.

2:16 Divide values: 72 ÷ 8 = 9.

2:21 Attach the negative sign: -9.

2:25 So the answer is -9.

2:28 Your turn. Calculate: -12 - (-7) Pause the video, and try it.

2:36 The answer is -5.

2:39 Well done! Now try the practice and the quiz in this lesson on LearnFun.