#1**+2 **

You need to use the perpendicular distance formula to find the distance between the line and the point (3,4)

That will be your radius.

Then it is the same as the last question.

Have a go.

Here is the formula with an example of how to use it.

Melody Nov 9, 2019

#2**0 **

Put the equation into y = mx + b form:

y = -2x +1 now you hve slope, m m = -2 the perpindicular slope will be - 1/m = -1/-2 = 1/2

Now you have a point (3,4 ) and the slope.... can you find the equation of the line with slope = 1/2 and point 3,4 ?

draw that line..... then you can find the radius of your circle quite easily.....

Remember the equation of a circle? (x-h)^2 + (y-k)^2 = r^2 ???? (h,k) is the center of the circle......

Let us know what you find for an answer.....

ElectricPavlov Nov 9, 2019

#4**+2 **

We can use the "formula" for the distance from a point to a line to solve this

The line is 2x + y -1 = 0

So we have that

l 2(3) + 4 - 1 l l 9 l 9

____________ = ____ = ___ this is the radius of the circle

√[2^2 + 1^2 ] √5 √5

The equation of the circle is

(x - 3)^2 + ( y - 4)^2 = 81/5

Here is a graph : https://www.desmos.com/calculator/b8fxaseqdv

CPhill Nov 9, 2019