What is the equation of a circle centered at the origin with radius 20.. i cant find the answer and i even tried?

Required equation of circle is x² + y² = 400

Step-by-step explanation:

We are given center of the circle i origin and radius = 20 units.

We have to find the equation of the circle.

We know that coordinates of the origin is ( 0 , 0 )

To write the equation of circle we use standard equation of circle,

Standard equation of circle is given as below,

( x - h )² + ( y - k )² = r²

here, ( h , k ) is coordinate of the center of the circle. and r is radius of the circle.

Using given information and standard equation of circle, we have

( x - 0 )² + ( y - 0 )² = 20²

x² + y² = 400

Therefore, Required equation of circle is x² + y² = 400

option c) graph of line going through 1, 4 and 3, 10

step-by-step explanation:

let y equal to margo's coin collection

let x equal to number of years

at the begining x=0, y=1 → point=(x,y)→point=(0,1)

she adds 3 coins per year, then y=1+3x

at x=1, y=1+3(1)=1+3→y=4→point=(x,y)→point=(1,4)

at x=3, y=1+3(3)=1+9→y=10→point=(x,y)→point=(3,10)

the graph of line going through (1, 4) and (3, 10), then the option c is the correct.