Solve whats in the parentheses first
5k+25+4<21+6k
5k+29<21+6k
plug in a number in k for both sides
5(1)+29<21+6(1)
5+29<21+6
34<27
5(2)+29<21+6(2)
10+29<21+12
39<33
so 5(k+5)+4 is greater than 21+6k
The average temperature is -7.
Hope this helps
so 21 - 13, the money will be invested for 8 years.

The answer is c because all you are doing here is subbing the variable r for 5b.
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