Х-9=56-20
х-9=36
х=36+9
х=45
13х=130
х=130:13
х=10
10х+20=180
10х=180-20
10х=160
х=160:10
х=16
х+7=60-34
х+7=26
х=26-7
х=19
3х=450-150
3х=300
х=300:3
х=100
40х=100000:25
40х=4000
х=4000:40
х=100
50:х=50-48
50:х=2
х=50:2
х=25
15-х=216:18
15-х=12
х=15-12
х=3
Ж) 7/11 * (3/7 + 5/7) = 7/11 * 8/7 = 8/11
1) 3/7 + 5/7 = 8/7
2) 7/11 * 8/7 = (1*8)/(11*1) = 8/11
з) (7/12 - 3/16 - 5/24) + 1/4 = 7/16
1) 7/12 - 3/16 = 28/48 - 9/48 = 19/48
2) 19/48 - 5/24 = 19/48 - 10/48 = 9/48 = 3/16
3) 3/16 + 1/4 = 3/16 + 4/16 = 7/16
<span>1) 63 - 19 = 44
2) 85 - 24 = 61
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