Question

The centre of circles at(0,0).And the circle passes through the point (-7,0).Then the area of the circle

Answer 1

Given:

Center of the circle = O(0,0)

Point through which the circle passes is P(-7,0)

To find:

Area of the circle = ?

Solution:

To find the area of the circle, we have the following formula:

$Area = \pi r^2$

Therefore, we need to have the value of radius of the circle.

Radius of a circle is nothing but the distance between the centre of the circle and any of the point through which the circle passes.

Here, we are given one point P(-7, 0) and circle's center O(0, 0).

We can use distance formula to find the radius OP.

Distance formula:

$D = \sqrt{(x_2-x_1)^2+(y_2-y_1)^2}\\x_1 = 0\\y_1 = 0\\x_2 = -7\\y_2 = 0$

$D = \sqrt{(-7-0)^2+(0-0)^2} = 7\ units$

So, the area is:

$Area = \dfrac{22}{7}\times 7^2\\\Rightarrow Area = \bold{154\ sq\ units}$