1)

7t=22,12

t=3.16

2)

6p=89.40

p=14.9

2t+5t+3.18=25.3

7t=22.12

t=3.16

проверка:   2*3,16+5*3,16+3,18=25,3

                   6,32+15,8+3,18=25,3

                      25,3=25,3

8p-2p-14,21=75,19

6p=89,4

p=14.9

проверка:  8*14,9-2*14,9-14,21=75,19

                 119,2-29,8-14,21=75,19

                     75,19=75,19