Question 362893
let Ben be x miles from home
then they will be x+1 miles away when Mary is 5 miles from home.
Since they are travelling east and north they form right triangle
Pythagoras theorem
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(x+1)^2=x^2+5^2
x^2+2x+1=x^2+25
2x=24
x= 12 miles
ben is 12 miles from home
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m.ananth@hotmail.ca