What is the length of X?

x = 85

Step-by-step explanation:

Its a Pythagorean theorem question, being a^2 + b^2 = c^2.

and knowing that 168 is the entire base we would divide by 2 to get 84 as b.

The new equation would be 13^2 + 84^2 = c^2

Then squaring them to get 169 + 7056 = c^2

Then add them together and square root them 7225 = c

The square root is 85 making it equal x.  

i leave the calculator work to you.

7. diameter 4 miles, circumference 4π miles

8. radius 0.2 miles, circumference 0.4π miles

[this is a bad problem because the actual radius of a car on the track is less than 0.2 miles so the answer is less than 0.4π miles]

9. radius 6 feet, circumference 12π feet

10. diameter 14 cm, circumference 14π cm

11. diameter 4.8 feet, circumference 4.8π feet

i think that you should ask google for the answer to that problem because if we don't know it google does