4000 is the answer to your question
Let
x-------> the first number
y------> the second number
we know that


equation 

equation 
substitute equation 1 in equation 2

using a graph tool-----> to resolve the second order equation
see the attached figure
the solution is

Answer:
Denote the amount of miles she will run in 24 minutes: x
=> x/24 = 7/60 (same rate)
=> x = 7x24/60 = 2.8 (miles)
Pythagorean Theorem
75^2+40^2=x^2
5625+1600=7225
Square root of 7225 is 85
So hypotenuse is 85 yd