Question

you have to know if these signs are for signed numbers or are they operational signs, -5+6-8+9-4=, how do you know which they are?

Answer 1

they are assumed to be operators unless you have a bracket or parentheses.

Answer 2

for example 1-2 versus 1(-2)
1-2 = -1
1(-2)= -2

Answer 3

normally it does'nt matter 1+-1=0 no matter wat

Answer 4

your calculator especially Ti calculators differentiate between a - and (-)
- is a subtraction operator
(-) is a negative sign

Answer 5

are you sure that-5 is a signed number and this would mean the operation is to subtract? 10(-)-5=15. in which case (-) is the operational sign and -5 is the signed number?