Imagine right triangle PHF, where P - park, H - home and F - football field, then PH, PF are legs and HF is hypotenuse . Denote point L to be library. You know that point L lies on the segment FH and FL=8, LH=2. Also you know that PL is an altitude to the hypotenuse.
Use the property of altitude drawn from the vertex of right angle to the hypotenuse (the length of the altitude is geometrical mean between legs' projections onto hypotenuse):
mi.
This means that the distance between park and libriry is 4 miles.
Consider right triangle PLF ( angle L is right angle and PF - hypotenuse). By the Pythagorean theorem,
mi. The distance between park and football field is 
miles.
Answer: the distance between park and libriry is 4 miles and the distance between park and football field is miles.
the inequality goes from -30 and all number up but not including -30 because it has open circle. so mark all number greater than -30
Once you do the math the answer will be
y=9/7x-11/7
You're looking for c, so you want to isolate it or get it by itself. To get rid of the /3 you multiply since the opposite of division is multiplication and to get rid of it, you do the opposite (like -9 you would add 9 to get it to 0). Now you are left with -19+c = 24 (the 24 is 8*3 because what you do to one side you do to the other. Now you get c by itself so you add 19 to both sides which leaves you with C= 43. Sorry if this was confusing!
That is a horizontal straight line, so the slope is 0.
