- 1. NCERT MATHS for Grade VII INTRODUCTION TO INTEGERS Visit us at: www.ffy.vpweb.in FFY Center for Learning welcomes You to learn VII MATHS (CBSE)!
- 2. Definition on Integers Positive number – a number greater than zero. 1 2 3 4 5 6 Negative number – a number less than zero. -6 -5 -4 -3 -2 -1 1 2 3 4 5 6 Opposite Numbers – numbers that are the same distance from zero in the opposite direction -6 -5 -4 -3 -2 -1 1 2 3 4 5 6 Absolute Value – The size of a number with or without the negative sign. The absolute value of9 or of –9 is 9.
- 3. Usage of Negative Integers Negative Numbers Are Used to Measure the Sea Level 30 20 10-10-20-30-40-50 Negative Numbers Are Used to Show the amount of Debt Let’s say your parents bought a car by getting a loan from the bank for $5,000. This amount borrowed from bank has to be specified as - $5,000 to show they still owe the bank. Hint: If you don’t see a negative or positive sign in front of a number it is positive. 9 without sign shows that it is a positive number
- 4. Integer Addition Rules Rule #1 – If the signs are the same, pretend as if the signs aren’t there. Add the numbers and then put the sign of the addends in front of your answer. -9 + -5 = ( 9 + 5 =14) = -14 Rule #2 – If the signs are different pretend as if the signs aren’t there. Subtract the smaller from the larger one and put the sign of the one with the larger absolute value in front of your answer. - 49 + 5 = (49 – 5 = 4) = -4
- 5. Solve the Problems given here Solve These Problems 3 + -5 5 – 3 -4 + 7 7 – 4 -6 + 7 5 + -9 One Way to Add Integers Is With a Number Line When the number is positive, count to the right. When the number is negative, count to the left.
- 6. Integer Subtraction Rules Rule #1: Subtracting a positive integer from another positive integer (a – b = c) is the same as adding a –ive integer to a positive integer. 2 – 7 is the same as 2 + (-7) = 7 - 2 = -5 Here are some more examples: 12 – 8 = 12 + (-8) = 4 3 – 11 = 3 + (-11) = -7 Try out these problems yourself! 8 – 12 22 – 30 17 – 3 52 – 5 5 – 2 = 3 To check if your answer is correct, add b and c, you will get (a = b + c) 5 = 2 + 3
- 7. Integer Subtraction Rules Rule #2 : Subtracting a negative number from a positive integer (a – (-b) = c) is the same as adding a positive. Change the signs and add. 2 – (-7) is the same as 2 + (+7) = 2 + 7 = 9! Here are some more examples: 12 – (-8) = 12 + (+8) = 20 3 – (-11) = 3 + (+11) = 14 Try out these problems yourself! 8 – (-12) 22 – (-30) 17 – (-3) 52 – (-5) 5 – (-2) = 7 To check if your answer is correct, add b and c, you will get a (a = b + c) 5 = -2 + 7
- 8. Integer Subtraction Rules Rule #3: Subtracting a positive integer from negative integer (-a – b = c) is the same as adding a +ive integers but the result is a –ive integer. -2 – 7 is the same as -2 + (-7) = -(7 + 2) = -9 Here are some more examples: -12 – 8 = -(12 + 8) = -20 -3 – 11 = -(3 + 11) = -14 Try out these problems yourself! -8 – 12 -22 – 30 -17 – 3 -52 – 5 -5 – 2 = -7 To check if your answer is correct, add b and c, you will get (a = b + c) -5 = 2 + (-7)
- 9. Integer Subtraction Rules Rule #4 : Subtracting a negative number from another negative integer (-a – (-b) = c) is the same as adding a positive to a negative integer (-a + b = c) -2 – (-7) is the same as -2 + 7 = 7 - 2 = 5 Here are some more examples: -12 – (-8) = -12 +8 = -(12-8) = -4 -3 – (-11) = -3 + 11 = 11-3 = 8 Try out these problems yourself! -8 – (-12) -22 – (-30) – 17 – (-3) –52 – (-5) -5 – (-2) = -3 To check if your answer is correct, add b and c, you will get a (a = b + c) -5 = -2 + -3
- 10. VII Mathematics (CBSE) Chapter 1 - INTEGERS Call us at : 99942 86194 This is all About Integer Addition and Subtraction!