Question

Simplify:

(1) (−8) + (−3)
(2) 13 − 15
(3) 6 − (−19)
(4) 10 + (−7)

Answer 1

(1) Since both the numbers are negative, we will add the their magnitudes and give the sum a negative sign.
8 + 3 = 11
∴ (–8) + (–3) = –11

(2) 13 + (–15)
Since one number is positive and the other negative, we will find the difference of the magnitudes by subtracting the smaller number from bigger one.
15 – 13 = 2
The result will have the same sign as that of the number with the greater magnitude.
∴ 13 + (–15) = –2

(3) 6 – (– 19)
It means adding the opposite of (–19) to 6.
i.e., 6 + 19 = 25 [∵ The additive inverse of (–19) is (+19)]
∴ 6 – (–19) = 25

(4) 10 + (–7)
Since one number is positive and the other negative, we will find the difference of the magnitudes by subtracting the smaller number from the bigger one.
10 – 7 = 3
The result will have the same sign as that of the number with the greater magnitude.
∴ 10 + (–7) = 3