SOLUTION: I need help please!!! I can't figure this out at all. While finding the amount of seed to plant his three suare wheat fields, Hank observed that the side of one field was 1 kilom

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Question 161327: I need help please!!! I can't figure this out at all.
While finding the amount of seed to plant his three suare wheat fields, Hank observed that the side of one field was 1 kilometer longer than the side of the smallest field and that the side of the largest field was 3 kilometers longer than the side of the smallest field. If the total area of the three fields is 38 square kilometers, then what is the area of each field?

Found 2 solutions by vleith, nerdybill:
Answer by vleith(2983) About Me  (Show Source):
You can put this solution on YOUR website!
Find the length of the side on each field.
Let X be the length of the smallest field.
You are told the second field has a side length 1 kilo longer. So its side is (X+1)
You are also told the third field has a side length of (X+3)
The area of a square is given by A+=+s%5E2 where s is the length of one side
The total area of all 3 fields is given as 38 Km^2.
All we need to do now is add the three fields and then solve for X
TotalArea+=+Area1+%2B+Area2+%2B+Area3
38+=+X%5E2+%2B+%28X%2B1%29%5E2+%2B+%28X%2B3%29%5E2+
38+=+X%5E2+%2B+%28X%5E2+%2B+2X+%2B1%29+%2B+%28X%5E2+%2B+6X+%2B+9%29
38+=+3X%5E2+%2B+8X+%2B+10+
0+=+3X%5E2+%2B+8X+-+28
0+=+%283X+%2B+14%29%28X+-+2%29
So either 3x%2B14+=+0 or X-2+=+0
Thus either x+=+-14%2F3 or X=2
Since the length cannot be negative, the answer must be 2.
The small field is 2x2, the middle one is 3x3 and the largest one is 5x5.
Is 4 + 9 + 25 = 38?

Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
Let x = length of side of smallest field
then because "the side of one field was 1 kilometer longer than the side of the smallest field"
x+1 = length of one field
and because "the largest field was 3 kilometers longer than the side of the smallest field."
x+3 = length of largest field
.
Area of each field is side^2:
x^2 + (x+1)^2 + (x+3)^2 = 38
expanding through FOIL:
x^2 + x^2+2x+1 + x^2+6x+9 = 38
combining like-terms:
3x^2 + 8x + 10 = 38
3x^2 + 8x - 28 = 0
(3x+14)(x-2) = 0
x = {-14/3, 2}
.
We can toss out the negative solution leaving us with:
x = 2 km
x^2 = 4 sq km (smallest field)
.
(x+1)^2 = x^2+2x+1 = 2^2+2(2)+1 = 4+4+1 = 9 sq km (one field)
.
(x+3)^2 = x^2+6x+9 = 2^2+6(2)+9 = 4+12+9 = 25 sq km (largest field)
.
Answer:
4 square kilometers
9 square kilometers
25 square kilometers