Question 887740
This is Easy!
Let Go.
==>The first step is to illustrate the question on your mind, by sketching a football field in your mind, it is RECTANGULAR right.
==>Second step is that for a shape which is rectangle it most posses a LENGHT=HEIGHT {the longest side} and a BREATH=WIDTH {the shortest side} right.
==>Third step is to divide rectangle into two from Two ALTERNATE ANGELS, 
Now we have a RIGHT-ANGLED TRIANGLE with a LENGHT, BREATH AND HYPOTENUSE.
==>Fourth step is to name each angle <A, <B, <C. 
==>Fifth step is to assign the numerical value to the  such that AB=8s {as it take 8 seconds for the player to cover the (width analogous to Breath) of the field}, BC=15s, and AC=x {unknown time in seconds}
==>Sixth step is for us to remember our PYTHAGORA's Theorem which says that IN A RIGHT-ANGLED TRIANGLE THE SQUARE OF THE LENGHTH OF THE HYPOTENUSE EQUALS THE RUN OF THE SQUARES OF THE OTHER TWO SIDES that is 
 H^2=L^2  B^2.
==>Seventh step is to apply this formula in our Question which will give 
 AC^2=AB^2    BC^2 that is 
 x^2=8^2   15^2.
==>For the last step is to solve the equation by finding our x 
x = sqrt{8^2  15^2}, henceforth we could solve our question effortlessly by finding the square of 8 and 15 which is 64 and 225 respectively to give
x = sqrt{64   225} then by performing our addition we have 64   225 = 289 which we slot in our working to have 
x = sqrt{289} and we find the square root of 289 which is 17 we have our 
x = 17 therefore our 
AC = 17s    

==>In Conclusion for the Player to run from one corner to the other {adjacent or opposite} corner it is Seventeen seconds.


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