SOLUTION: Hank has three square fields. One field is 1 kilometer longer than the side of the smallest field. The side of the largest field is 3 kilometers longer than the smallest field. The

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: Hank has three square fields. One field is 1 kilometer longer than the side of the smallest field. The side of the largest field is 3 kilometers longer than the smallest field. The      Log On


   



Question 151761: Hank has three square fields. One field is 1 kilometer longer than the side of the smallest field. The side of the largest field is 3 kilometers longer than the smallest field. The total area of the fields is 38 square kilometers . What is the area of each field? This doesn't sound like it should be difficult but I can't figure it out. A=S^2 ???? 38= S^2 + S^2+1^2 + S^2 +3^2 ???
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
It can get confusing.
First name the sides of the fields.
How about S for small field, L for large field, and M for the middle field.
Since they're squares the area of each field is,
A%5BS%5D=S%5E2
A%5BM%5D=M%5E2
A%5BL%5D=L%5E2
The largest field side is 3 km larger than the small field.
L=S%2B3
One field is 1 kilometer longer than the side of the smallest field.
I'm assuming this is the middle field.
M=S%2B1
The total area is 38 km^2.
S%5E2%2BM%5E2%2BL%5E2=38
Now substitute for M and L.
S%5E2%2BM%5E2%2BL%5E2=38
S%5E2%2B%28S%2B1%29%5E2%2B%28S%2B3%29%5E2=38
Note the expansion of the squares.
Check on the FOIL method if this isn't clear.
S%5E2%2Bhighlight%28S%5E2%2B2S%2B1%29%2Bhighlight%28S%5E2%2B6S%2B9%29=38
3S%5E2%2B8S%2B10=38
3S%5E2%2B8S-28=0
You can factor this quadratic equation.
%283S%2B14%29%28S-2%29=0
Two solutions:
3S%2B14=0
S=-14%2F3
A negative length does not make sense in this case so we throw out that answer.
S-2=0
highlight%28S=2%29
Then from above,
M=S%2B1
M=2%2B1
highlight%28M=3%29
and finally
L=S%2B3
L=2%2B3
highlight%28L=5%29
A%5BS%5D=S%5E2=2%5E2=4
A%5BM%5D=M%5E2=3%5E2=9
A%5BL%5D=L%5E2=5%5E2=25
The smallest field is 4 km^2, the middle field is 9 km^2, and the large field is 25 km^2.