Answer:1.5
Step-by-step explanation:
Answer:

Step-by-step explanation:

Answer:
18
Step-by-step explanation:
21-n; n=3
Substitute n for 3:
Solve.
Answer:
Step-by-step explanation:
the 3 equation can not be factorised. Because they will result to fraction
Answer:
k-5. The question seems incomplete though.