Answer:
The answer is D.
Step-by-step explanation:
Well I don't know where inequalities would come in but the third length would be solved as follows.
a^2+b^2=c^2
10^2+18^2=424

Answer;

I hope this is correct, its what I would do if I had this equation.
Try this: Combine 6 and 9, obtaining 15.
Compare this sum, 15, to the length of the 3rd side: 15.
If placed end to end, the 2 sides with lengths 6 and 9 form a new line of length 15. We'd end up with this new line superimposed on the 3rd side (with length 15).
Think: Do 2 straight lines of length 15, superimposed on one another, form a triangle?
Answer:
585
Step-by-step explanation:
9 * 13 * 5 = 585
9 FLIGHTS OF STAIRS
13 STEPS IN EACH FLIGHT
5 DAYS
Hope this helps!
From V
$6.8 would be it if I’m not wrong just tel me but I rounded to 17$