Question

The area of a rectangular field is 875 m2. Two adjacent sides of the field are fenced with wood costing $5/m. The remaining two sides are fenced with steel costing $10/m. The total cost of the fencing is $900. What are the dimensions of the field?

Answer 1

Let the dimensions be A x B (or a x b).

ab = 875
15a + 15b = 900 [ from 10a + 5a + 10b + 5b = 900 ]
a + b = 60
a (60 - a) = 875
60a - a^2 = 875
a^2 - 60a + 875 = 0

Dimensions are 35 x 25 = 875
15 * (35 + 25) = 15 * 60 = 900

Answer 2

Thank you so much!! :)

Answer 3

you welcome (: