(x-16)×9=126
28×(x+5)=224
(x+76):7=15​

1) (х - 16) * 9 = 126

   х - 16 = 126 : 9

   х - 16 = 14

   х = 16 + 14

   х = 30

2) 28 * (х + 5) = 224

   х + 5 = 224 : 28

   х + 5 = 8

   х = 8 - 5

   х = 3

3) (х + 76) : 7 = 15

    х + 76 = 15 * 7

    х + 76 = 105

    х = 105 - 76

    х = 29

(x-16)×9=126 28×(x+5)=224 (x+76):7=15

x-16=126:9 x+5=224:28 x+76=15×7

x-16=14 x+5=8 x+76=105

x=16+14 x=8-5 x=105-76

x=39 x=3 x=29