Question 631601
Since Mary and her husband have to go at right angles to each other to their work place, at any given position,

Mary, husband and home form a right triangle.

So we can use Pythagoras theorem
Juan's distance from home be x
Mary 5 miles from home
the distance betwen them = (x+1) 

{{{x^2+5^2= (x+1)^2}}}

{{{x^2+25 = x^2+2x+1}}}

2x+1=25
2x=24
/2
x=12 miles


Juan is 12 miles from home

m.ananth@hotmail.ca