Answer:
The measure of the shortest side is 851 miles
Step-by-step explanation:
Let
x ----> the measure of the shortest side
y ---> the measure of the middle side
z ---> the measure of the longest side
we know that
The perimeter of triangle is equal to


so
----> equation A
the shortest side measures 71 mi less than the middle side
so
----> equation B
the longest side measures 372 mi more the the middle side
so
----> equation C
substitute equation B and equation C in equation A

solve for y

Find the value of x

therefore
The measure of the shortest side is 851 miles
3 because 3•3 is 9 and 9•3 is 27
The equation should be 7x^2 -x-9=0