Exercise 6.4

Find:

(i) 40 – (22)

Answer:

40 – (22)
= 40 + (additive inverse of 22)
= 40 – 22
=

(ii) 84 – (98)

Answer:
= 84 + (additive inverse of 98)
= 84 – 98
=

(iii) (-16) + (-17)

Answer:
(-16) + (-17)
= -16 – 17
=

(iv) (-20) – (13)

Answer:
(-20) – (13)
= -20 + (additive inverse of 13)
= -20 - 13
=

(v) 38 – (-6)

Answer:
38 – (-6)
= 38 + (additive inverse of -6)
= 38 + 6
=

(vi) (-17) – (-36)

Answer:
(-17) – (-36)
= -17 + (additive inverse of -36)
= -17 + 36
=

Fill in the blanks with appropriate >, < or = sign:

Answer:

(i) (-4) + (-5) <>= (-5) - (-4)

(ii) (-16) - (-23) <>= (-6) + (-12)

(iii) 44 - (-10) <>= 47 + (-3)

(iv) (-21) + (-22) <>= (-22) + (-21)

Fill in the blanks with the appropriate numbers.

Answer:

(i) (-13) + = 0

(ii) (-16) + (16) =

(iii) (-5) + = –14

(iv) – 16 = –22

Simplify:

(i) (-6) – (+5) – (+2)

Answer:
(-6) – (+5) – (+2)
= -6 - 5 - 2
=

(ii) (-12) + 42 – 7 – 2

Answer:
(-12) + 42 – 7 – 2
= (-12 - 7 - 2) + 42
= -21 + 42
=

(iii) (-3) + (-6) + (-24)

Answer:
(-3) + (-6) + (-24)
= -3 - 6 - 24
=

(iv) 40 – (-50) – (2)

Answer:
40 – (-50) – (2)
= 40 + 50 - 2
= 90 - 2
=