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.
Answer:
Choice A
Step-by-step explanation:
When you have two shapes that are similar their sides are always proportional. So all we have to do is set up a proportion.

Now we cross multiply and solve

And that's it x equals 6 feet.
Answer:
y= (3/4) x - (3/2)
Step-by-step explanation:
3x - 4y = 6 (using algebra add the 4y to the other side & subtract the 6 to the other side >> 3x - 6 = 4y (then divide everything by 4 to get y by itself) >> 3/4x - 6/4 = y (then simplify) >> 3/4x - 3/2 = y
Answer:
Y=21
Step-by-step explanation:
add 13 on both sides you get Y=21
Answer:
11
Step-by-step explanation: