Question 241893
First, we must remember these rules:
a. when we have a positive sign in front of a parenthesis and a positive number inside the parenthesis, the result is a positive number.
b. when we have a positive sign in front of a parenthesis and a negative number inside the parenthesis, the result is a negative number.
c. when we have a negative sign in front of a parenthesis and a positive number inside the parenthesis, the result is a negative number.
d. when we have a negative sign in front of a parenthesis and a negative number inside the parenthesis, the result is a positive number.
.
In summary:
+(+) = +
+(-) = -
-(+) = -
-(-) = +
.
So, let's solve your problem:
{{{17+(-47)+357+(-585)+85+(-429)}}}
{{{17-47+357-585+85-429}}}
We can solve all at once by using a calculator, or solve two terms at a time if you don't have a calculator or are not allow to use one during your tests.  I'll do the long way here.
{{{-30+357-585+85-429}}}
{{{327-585+85-429}}}
{{{-258+85-429}}}
{{{-173-429}}}
{{{-602}}}
.
Done!