The center of circle d is (0,0). the circumference of the circle passes through point e (-7,-4). find the length of the radius of circle d.

Step-by-step explanation:

The radius of circle D is the distance from the origin to (-4, -7).

In math, the distance formula gives us the distance between two points, (x₁, y₁) and x₂, y₂):

You are really using Pythagoras' Theorem to find the distance. You are building a right triangle whose hypotenuse connects two given points.  

For example, in the blue triangle below, the distance between the points (0,0) and (-4, -7) is