230k views
1 vote
Riley has a farm on a rectangular piece of land that is 200200200 meters wide. This area is divided into two parts: A square area where she grows avocados (whose side is the same as the length of the farm), and the remaining area where she lives.

Every week, Riley spends \$3$3dollar sign, 3 per square meter on the area where she lives, and earns \$7$7dollar sign, 7 per square meter from the area where she grows avocados. That way, she manages to save some money every week.



Write an inequality that models the situation. Use lll to represent the length of Riley's farm.

User Ahuemmer
by
4.6k points

2 Answers

7 votes

Answer:

Answer is in attached image.

Riley has a farm on a rectangular piece of land that is 200200200 meters wide. This-example-1
User Richard Bonneau
by
4.3k points
5 votes

Answer:

The inequality that models the situation for her to have money to save is

7L² > 3(200L - L²)

On simplifying and solving,

L > 60 meters

Explanation:

The length of her farm = L meters

The farm where she grows avocados is of square dimension

Area of the farm = L × L = L²

The piece of land is 200 m wide.

Total area of the piece of land = 200 × L = (200L) m²

If the area of her farm = L²

Area of the side where she lives will be

(Total area of the land) - (Area of the farm)

= (200L - L²)

= L(200 - L)

Every week, Riley spends $3 per square meter on the area where she lives, and earns $7 per square meter from the area where she grows avocados.

Total amount she earns from the side she grows the avocados = 7 × L² = 7L²

Total amount she spends on the side where she lives = 3 × (200L - L²) = 3(200L - L²)

For her to save money, the amount she earns must be greater than the amount she spends, hence the inequality had to be

(Amount she earns) > (Amount she spends)

7L² > 3(200L - L²)

To simplify,

7L² > 3L(200 - L)

Since L is always positive, we can divide both sides by L

7L > 3(200 - L)

7L > 600 - 3L

10L > 600

L > 60 meters

Hope this Helps!!!

User Alokoko
by
3.8k points