44 + b = 64

(a)  

78 + b = 108

(a)  

e + 55 = 75

(a)  

f + 73 = 93

(a)  

64 - a = 44

(a)  

85 - b = 5

(a)  

61 - c = 11

(a)  

d - 20 = 80

(a)  

d - 32 = 60

(a)  

d - 55 = 40

(a)  

d - 55 = 23

(a)  

f - 23 = 45

(a)  

85 - b = 23

(a)  

56 + a = 99

(a)  

f + 73 = 90

(a)