Take the root of both sides and solve.
c = - 7 sqr root 5
c = -1.258
The standard form of the equation of a circle is:

Where the point (a,b) represents the centre and r is the radius. So, given your information, the equation will be:
Answer:
5 hours
Step-by-step explanation:
We can write a ratio
20 laps 100 laps
-------------- = --------------
1 hour x hours
Using cross products
20x = 100
Divide by 20
20x/20 = 100/20
x = 5 hours
Answer:

Step-by-step explanation:
1) the rule of transformation [degr → rad] is:
![\alpha [rad]=\alpha [degr] *\frac{\pi }{180};](https://tex.z-dn.net/?f=%5Calpha%20%5Brad%5D%3D%5Calpha%20%5Bdegr%5D%20%2A%5Cfrac%7B%5Cpi%20%7D%7B180%7D%3B)
2) according to the formula above:
230°=230*π/180=23π/18 [rad].