SOLUTION: Solving Problems with Quadratic Equations 12. A rectangular construction site is enclosed on three sides using 1200 m of fencing. The remaining side is formed by an existing wall.

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: Solving Problems with Quadratic Equations 12. A rectangular construction site is enclosed on three sides using 1200 m of fencing. The remaining side is formed by an existing wall.      Log On


   

Question 198589: Solving Problems with Quadratic Equations
12. A rectangular construction site is enclosed on three sides using 1200 m of fencing. The remaining side is formed by an existing wall. What dimensions enclose 180 000m^2 of land?
Answer by arallie(162) About Me  (Show Source):
You can put this solution on YOUR website!
Here we go:
If2l%2Bw=1200 and lw=180000
Then w=1200-2l
Substitute and solve
l%281200-2l%29=180000
-2l%5E2%2B1200l-180000=0
Simplify
l%5E2-600l%2B90000=0
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ when a=1, b=-600, c=90000
Therefore
Real solutions:
Root 1: 300
Substitute and solve
2%28300%29%2Bw=1200
600%2Bw=1200
w=600
Check
300%28600%29=180000
180000=180000
Check
Anymore questions feel free to ask me.
Anthony Allie
arallie@gmail.com
http://arallie.webs.com/tutoring.htm