Question

х+(45-30)=75
35+23+х=100
70-х=8+9+2​

Answer 1

$1)x+(45-30)=75\\x+15=75\\x=75-15\\x=60\\2)35+23+x=100\\58+x=100\\x=100-58\\x=42\\3)70-x=8+9+2\\70-x=19\\-x=19-70\\-x=-51\\x=51$

Answer 2

Ответ:

1) x+(45-30)=75

x+15=75

x=75-15

x=60

2) 35+23+x=100

58+x=100

x=100-58

x=42

3) 70-x=8+9+2

70-x=19

x=70-19

x=51