A square has 2 pairs of parallel lines
Answer:9
Step-by-step explanation:
Use the pythagorean theorem. 
We know both a and c, so it becomes
=
16+b^2=97=
97-16=b^2=
81=b^2=
9=b
The final marker would be 105 miles from the first marker. Hope this helped. (5x21=105)
Answer:9x-9=7 or 9x-9=-7
Step-by-step explanation:
An absolute value is the distance from zero, therefore the answer can not be negative. In this case, 9x-9=7 and 9x-9=-7 both work, because 7 and -7 are the same distance from zero.