Question 27308
Start by drawing this out.  Make a line going up your page for a ways, then over to the right, then connect that to where you startes, so you have an upside-down right triangle.  Label the vertical side 65 km and the horizontal side 75 km.  The length of the hypotenuse (the longest side) is your distance from your starting point.

The formula for finding out the lengths of the sides of a right triangle is {{{a^2+b^2=c^2}}}.  So you have {{{65^2+75^2=c^2}}}.  

Multiply that out and you have {{{4225+5625=c^2}}}.

Add to get {{{9850=c^2}}}.

Then find the square root of both sides {{{sqrt(9850)=sqrt(c^2)}}}.

c=99.247 km, or however many decimal places you're supposed to round to.