A vertical linehas undefined slope because all points on the line have the same x-coordinate.
Answer:
7.5
Step-by-step explanation:
(15/5)-0.4-0.4-0.4-0.4-0.4-0.4-0.4-0.2=0
about 500
54 is about equal to 50 and 12 is about equal to 10, 50*10 = 500
Here's the method on the first one (36)
The ratio is

, hence if we call

the number below

, we will have

hence

I_72__I_36_I_24_I_12_I
<span>I_126_I_
63_I_42_I_21_I
</span>