Question

Write the standard equation of the circle with center (-3, 5) and a diameter of 10.

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Answer 1

The general equation of circle with center (a,b) and radius r is given by

`(x-a)^2+(y-b)^2=r^2`

We know that radius = diameter /2 =10/2=5

Thus the equation of circle with center (-3,5) and radius 5 is given by

`(x-(-3))^2+(y-5)^2=5^2`

`(x+3)^2+(y-5)^2=25`

When expanding this, we get

x^2+6x+9+y^2-10y+25=25

x^2+y^2+6x-10y+9=0

This is the required equation of circle.