Here's your mistake:
7t = -112
It should be
-7t = -112
t = +16
7(4 - t) = -84
i got:
28 - 7t = -84
-28 = -28
7t = -112
----- -----
7 = 7
t = -16
is this right : -16
3 answers
oh ok i see thanks can you check another:
-5.5 (8+b) = -33
i got:
-44 + -5.5b = -33
+44 +44
__________________
-5.5b = 11
___________
- 5.5 = 5.5
b = -2
-5.5 (8+b) = -33
i got:
-44 + -5.5b = -33
+44 +44
__________________
-5.5b = 11
___________
- 5.5 = 5.5
b = -2
Right!