If you would like to calculate twenty two less than three times a number is -70, you can do it using the following steps:
a number ... n
three times a number ... 3 * n
twenty two less than three times a number ... 3 * n - 22
is -70 ... = -70
3 * n - 22 = -70
3 * n = -70 + 22
3 * n = -48 /3
n = -48 / 3
n = -16
The number you are looking for is -16.