Answer:
r=5
Step-by-step explanation:
centre is (1,3)
r=√((4-1)²+(7-3)²)=√(9+16)=√25=5
r=5
The radius of the given circle with point B(4,7) lying on its circumference is 5 units.
The equation of the circle is:
[tex](x-1)^{2} +(y-3)^2=r^{2}[/tex]......(1)
A circle is a locus of a point the distance of which from a fixed point always remains constant.
Since point B (4,7) lies on the circle so this point will satisfy the equation of the circle.
By putting (4,7) in (1) we get
[tex](4-1)^{2} +(7-3)^2=r^{2}[/tex]
[tex]r^{2} =25[/tex]
So, [tex]r=5[/tex]
Hence, the radius of the given circle is 5 units.
To get more about circles visit:
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