Question

Calculați pe a:
a - (27 +39) =18
(28 +46) - a=57
a +(14 + 16)=90
(93-78) + a= 72
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Answer 1

a-(27+39)=18

a-65=18

a=18+65

a=83

(28+46)-a=57

74-a=57

a=74-57

a=17

a+(14+16)=90

a+30=90

a=90-30

a=60

(93-78)+a=72

15+a=72

a=72-15

a=57

Answer 2

1) 27+39+ 18=84

V.84-(27+39)=18

2).28+46-57=17

V.(28+46)-17=57

3) 14+16+90=120

v.120-(14+16)=90

4). 93-78=15

72-15=57

V.(93-78)+57=72