Реши уравнение номер9

1. (5•а-25):4 = 29 -4• 6
5a-25 :4 = 5
5a -25 = 20
5a = 20+25
5a= 45
a= 45:5
a= 9
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2. 39 + a • (42 : 7) - ( 19 + 18) = 26
39 + a • 6 -37 = 26
39 + 6a -37 = 26
2 + 6a = 26
6a = 26-2
6a = 24
a= 24:6
a = 4
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