1- 3.1 = what - 1.5
2- 6.4 = what + 2.6

other questions

3- x − 8 = -3

4- -7 = what - 7

5- -15 = what + 13

6- what - 10 = - 1

7- -1 - what = -8

8- -25 + x = -8

9- -14 + what = 10

10- -30 − what = -25

11- what − 20 = -6