Question

Write the equation, please.

Answer 1

`\displaystyle {x}^(2) + {y}^(2) = 49`

Explanation:

we are given a circle

we want to figure out the equation of the circle

remember that,

`\rm \displaystyle E _(c) : (x - {h)}^(2) + (y - k {)}^(2) = {r}^(2)`

(h,k) are the centre of the circle

we can clearly see that the centre of the circle is (0,0) and the redious is 7 units

thus substitute:

`\displaystyle (x - {0)}^(2) + (y - 0{)}^(2) = {7}^(2)`

further simplification is needed:

`\displaystyle {x}^(2) + {y}^(2) = 49`

and we are done!

Answer 2

x^2+y^2 = 49

Explanation:

This is a circle.

The generic equation of a circle is

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

where (h,k) is the center and r is the radius

The center of the circle is at the origin which is (0,0)

The radius is 7

(x-0)^2+(y-0)^2 = 7^2

x^2+y^2 = 49