Question

1. Which of the following correctly gives the center and radius of the circle defined by the equation(x-7)2 + (x-2)2 = 10?

Answer 1

The general equation of the circle with centre (h,k) and radius r is,

`(x-h)^2+(y-k)^2=r^2`

Simplify the given equation to obtain the equation in general equation.

`\begin{gathered} (x-7)^2+(y-2)^2=10 \\ (x-7)^2+(y-2)^2=(\sqrt[]{10})^2 \end{gathered}`

On compare the equation with general equation the centre and radius is,

`(h,k)=(7,2)`

And

`r=\sqrt[]{10}`

So centre is (7,2) and radius is

`\sqrt[]{10}`

Option B is correct answer.