Find all points $(x,y)$ that are $5$ units away from the point $(2,7)$ and that lie on the line $y = 5x - 28.$
First, let's make some observations about this question.
All points 5 units away from point (2, 7) would make a circle with center (2, 7) and radius 5.
The formula for that circle would look something like \((x-2)^2+(y-7)^2=25\)
Now, combining that with the second equation, and we get a system.
Subsituting out y with the x values in the line equation, we get
\((x-2)^2+(5x-35)^2=25\)
Simplifying, and we get
\(13x^{2}-177x+602=0\)
Using the quadratic equation, we find two values of x. We get
\(x=7\\ x=\frac{86}{13}\)
Plugging these x values into the second equation where we isolated y, we get that \(y=7;y=\frac{66}{13}\)
So our final two answers are (7, 7) and (86/13, 66/13)
Thanks! :)