SOLUTION: What is the radius of a circle if the end points of a diameter are K(-1,4) and J(7,4). Then find the radius of a circle with the cirumfrance of 17pie cm. Wasnt in school

Algebra ->  Circles -> SOLUTION: What is the radius of a circle if the end points of a diameter are K(-1,4) and J(7,4). Then find the radius of a circle with the cirumfrance of 17pie cm. Wasnt in school       Log On


   



Question 197782: What is the radius of a circle if the end points of a diameter are K(-1,4) and J(7,4). Then find the radius of a circle with the cirumfrance of 17pie cm.



Wasnt in school for this lesson and my book is confusing me. Help would greatly appreciated.

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


If you know the measure of the diameter, you simply divide by 2 to get the measure of the radius. Knowing the endpoints of a segment allows you to find the measure of the segment by use of the distance formula:



where and are the coordinates of the given points. In this case, the endpoints of your diameter. Just plug in the values and do the arithmetic.

The circumference of a circle is given by the formula:



But you can solve this formula for and then use it to find the radius when you know the circumference. Just divide both sides by



Again, just plug in the numbers you know and do the arithmetic.


John