Label the points A,B,C
- A = (1,2)
- B = (4,5)
- C = (8,9)
Let's find the distance from A to B, aka find the length of segment AB.
We use the distance formula.

Segment AB is exactly
units long.
Now let's find the distance from B to C

Segment BC is exactly
units long.
Adding these segments gives

----------------------
Now if A,B,C are collinear then AB+BC should get the length of AC.
AB+BC = AC
Let's calculate the distance from A to C

AC is exactly
units long.
Therefore, we've shown that AB+BC = AC is a true equation.
This proves that A,B,C are collinear.
For more information, check out the segment addition postulate.
Answer:
Yes
Step-by-step explanation:
Answer:
Equation of circle in standard form with centre (0, – 10) and radius 6. 
Step-by-step explanation:
We need to write equation of circle in standard form with centre (0, – 10) and radius 6.
The equation of circle is: 
where (h,k) is centre of circle and r is radius
We are given centre (0,-10) so, h=0, k=-10 and radius r = 6
Putting values and finding equation:

So, equation of circle in standard form with centre (0, – 10) and radius 6. 