Answer:
![y=-\sqrt{3}x+2](https://tex.z-dn.net/?f=y%3D-%5Csqrt%7B3%7Dx%2B2)
Step-by-step explanation:
We want to find the equation of a straight line that cuts off an intercept of 2 from the y-axis, and whose perpendicular distance from the origin is 1.
We will let Point M be (x, y). As we know, Point R will be (0, 2) and Point O (the origin) will be (0, 0).
First, we can use the distance formula to determine values for M. The distance formula is given by:
![\displaystyle d=\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20d%3D%5Csqrt%7B%28x_2-x_1%29%5E2%2B%28y_2-y_1%29%5E2%7D)
Since we know that the distance between O and M is 1, d=1.
And we will let M(x, y) be (x₂, y₂) and O(0, 0) be (x₁, y₁). So:
![\displaystyle 1=\sqrt{(x-0)^2+(y-0)^2}](https://tex.z-dn.net/?f=%5Cdisplaystyle%201%3D%5Csqrt%7B%28x-0%29%5E2%2B%28y-0%29%5E2%7D)
Simplify:
![1=\sqrt{x^2+y^2}](https://tex.z-dn.net/?f=1%3D%5Csqrt%7Bx%5E2%2By%5E2%7D)
We can solve for y. Square both sides:
![1=x^2+y^2](https://tex.z-dn.net/?f=1%3Dx%5E2%2By%5E2)
Rearranging gives:
![y^2=1-x^2](https://tex.z-dn.net/?f=y%5E2%3D1-x%5E2)
Take the square root of both sides. Since M is in the first quadrant, we only need to worry about the positive case. Therefore:
![y=\sqrt{1-x^2}](https://tex.z-dn.net/?f=y%3D%5Csqrt%7B1-x%5E2%7D)
So, Point M is now given by (we substitute the above equation for y):
![M(x,\sqrt{1-x^2})](https://tex.z-dn.net/?f=M%28x%2C%5Csqrt%7B1-x%5E2%7D%29)
We know that Segment OM is perpendicular to Line RM.
Therefore, their <em>slopes will be negative reciprocals</em> of each other.
So, let’s find the slope of each segment/line. We will use the slope formula given by:
![\displaystyle m=\frac{y_2-y_1}{x_2-x_1}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20m%3D%5Cfrac%7By_2-y_1%7D%7Bx_2-x_1%7D)
Segment OM:
For OM, we have two points: O(0, 0) and M(x, √(1-x²)). So, the slope will be:
![\displaystyle m_{OM}=\frac{\sqrt{1-x^2}-0}{x-0}=\frac{\sqrt{1-x^2}}{x}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20m_%7BOM%7D%3D%5Cfrac%7B%5Csqrt%7B1-x%5E2%7D-0%7D%7Bx-0%7D%3D%5Cfrac%7B%5Csqrt%7B1-x%5E2%7D%7D%7Bx%7D)
Line RM:
For RM, we have the two points R(0, 2) and M(x, √(1-x²)). So, the slope will be:
![\displaystyle m_{RM}=\frac{\sqrt{1-x^2}-2}{x-0}=\frac{\sqrt{1-x^2}-2}{x}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20m_%7BRM%7D%3D%5Cfrac%7B%5Csqrt%7B1-x%5E2%7D-2%7D%7Bx-0%7D%3D%5Cfrac%7B%5Csqrt%7B1-x%5E2%7D-2%7D%7Bx%7D)
Since their slopes are negative reciprocals of each other, this means that:
![m_{OM}=-(m_{RM})^{-1}](https://tex.z-dn.net/?f=m_%7BOM%7D%3D-%28m_%7BRM%7D%29%5E%7B-1%7D)
Substitute:
![\displaystyle \frac{\sqrt{1-x^2}}{x}=-\Big(\frac{\sqrt{1-x^2}-2}{x}\Big)^{-1}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Cfrac%7B%5Csqrt%7B1-x%5E2%7D%7D%7Bx%7D%3D-%5CBig%28%5Cfrac%7B%5Csqrt%7B1-x%5E2%7D-2%7D%7Bx%7D%5CBig%29%5E%7B-1%7D)
Now, we can solve for x. Simplify:
![\displaystyle \frac{\sqrt{1-x^2}}{x}=\frac{x}{2-\sqrt{1-x^2}}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Cfrac%7B%5Csqrt%7B1-x%5E2%7D%7D%7Bx%7D%3D%5Cfrac%7Bx%7D%7B2-%5Csqrt%7B1-x%5E2%7D%7D)
Cross-multiply:
![x(x)=\sqrt{1-x^2}(2-\sqrt{1-x^2})](https://tex.z-dn.net/?f=x%28x%29%3D%5Csqrt%7B1-x%5E2%7D%282-%5Csqrt%7B1-x%5E2%7D%29)
Distribute:
![x^2=2\sqrt{1-x^2}-(\sqrt{1-x^2})^2](https://tex.z-dn.net/?f=x%5E2%3D2%5Csqrt%7B1-x%5E2%7D-%28%5Csqrt%7B1-x%5E2%7D%29%5E2)
Simplify:
![x^2=2\sqrt{1-x^2}-(1-x^2)](https://tex.z-dn.net/?f=x%5E2%3D2%5Csqrt%7B1-x%5E2%7D-%281-x%5E2%29)
Distribute:
![x^2=2\sqrt{1-x^2}-1+x^2](https://tex.z-dn.net/?f=x%5E2%3D2%5Csqrt%7B1-x%5E2%7D-1%2Bx%5E2)
So:
![0=2\sqrt{1-x^2}-1](https://tex.z-dn.net/?f=0%3D2%5Csqrt%7B1-x%5E2%7D-1)
Adding 1 and then dividing by 2 yields:
![\displaystyle \frac{1}{2}=\sqrt{1-x^2}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Cfrac%7B1%7D%7B2%7D%3D%5Csqrt%7B1-x%5E2%7D)
Then:
![\displaystyle \frac{1}{4}=1-x^2](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Cfrac%7B1%7D%7B4%7D%3D1-x%5E2)
Therefore, the value of x is:
![\displaystyle \begin{aligned}\frac{1}{4}-1&=-x^2\\-\frac{3}{4}&=-x^2\\ \frac{3}{4}&=x^2\\ \frac{\sqrt{3}}{2}&=x\end{aligned}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Cbegin%7Baligned%7D%5Cfrac%7B1%7D%7B4%7D-1%26%3D-x%5E2%5C%5C-%5Cfrac%7B3%7D%7B4%7D%26%3D-x%5E2%5C%5C%20%5Cfrac%7B3%7D%7B4%7D%26%3Dx%5E2%5C%5C%20%5Cfrac%7B%5Csqrt%7B3%7D%7D%7B2%7D%26%3Dx%5Cend%7Baligned%7D)
Then, Point M will be:
![\begin{aligned} \displaystyle M(x,\sqrt{1-x^2})&=M(\frac{\sqrt{3}}{2}, \sqrt{1-\Big(\frac{\sqrt{3}}{2}\Big)^2)}\\M&=(\frac{\sqrt3}{2},\frac{1}{2})\end{aligned}](https://tex.z-dn.net/?f=%5Cbegin%7Baligned%7D%20%5Cdisplaystyle%20M%28x%2C%5Csqrt%7B1-x%5E2%7D%29%26%3DM%28%5Cfrac%7B%5Csqrt%7B3%7D%7D%7B2%7D%2C%20%5Csqrt%7B1-%5CBig%28%5Cfrac%7B%5Csqrt%7B3%7D%7D%7B2%7D%5CBig%29%5E2%29%7D%5C%5CM%26%3D%28%5Cfrac%7B%5Csqrt3%7D%7B2%7D%2C%5Cfrac%7B1%7D%7B2%7D%29%5Cend%7Baligned%7D)
Therefore, the slope of Line RM will be:
![\displaystyle \begin{aligned}m_{RM}&=\frac{\frac{1}{2}-2}{\frac{\sqrt{3}}{2}-0} \\ &=\frac{\frac{-3}{2}}{\frac{\sqrt{3}}{2}}\\&=-\frac{3}{\sqrt3}\\&=-\sqrt3\end{aligned}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Cbegin%7Baligned%7Dm_%7BRM%7D%26%3D%5Cfrac%7B%5Cfrac%7B1%7D%7B2%7D-2%7D%7B%5Cfrac%7B%5Csqrt%7B3%7D%7D%7B2%7D-0%7D%20%5C%5C%20%26%3D%5Cfrac%7B%5Cfrac%7B-3%7D%7B2%7D%7D%7B%5Cfrac%7B%5Csqrt%7B3%7D%7D%7B2%7D%7D%5C%5C%26%3D-%5Cfrac%7B3%7D%7B%5Csqrt3%7D%5C%5C%26%3D-%5Csqrt3%5Cend%7Baligned%7D)
And since we know that R is (0, 2), R is the y-intercept of RM. Then, using the slope-intercept form:
![y=mx+b](https://tex.z-dn.net/?f=y%3Dmx%2Bb)
We can see that the equation of Line RM is:
![y=-\sqrt{3}x+2](https://tex.z-dn.net/?f=y%3D-%5Csqrt%7B3%7Dx%2B2)