They did it the long way.
The formula for the distance from a point to a line is
where the equation of the line is Ax+By+C=0 and the point is (x1,y1)
The point is (x1,y1) = (6,-3)
The line's equation is y=2x-5. we must get that in the form
Ax+By+C=0
y=2x-5. We subtract the entire right side from both sides
-2x+y+5=0
A=-2, B=1, C=5, (x1,y1) = (6,-3)
We can rationalize the denominator by multiplying by .
.
That's about 4.47, so let's draw the graph as a check:
That green line looks like it's about 4.47 units in length.
Edwin