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Set up an equation and solve.A rectangular plot of land has a width that is 25 meters less than its length. If the area of the plot5100 square meters, find the length and the width of this plot.

User Mselmi Ali
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1 Answer

8 votes
8 votes

Answer:

Width = 60

Length = 85

Step-by-step explanation:

Let L represent the length of the rectangular plot.

From the information given, the plot has a width that is 25 meters less than its length. This means that

Width = L - 25

Recall, the formula for calculating the area of a rectangle is expressed as

Area = length x width

If the area of the plot is 5100 square meters, the required equation would be

L(L - 25) = 5100

By expanding the parentheses, it becomes

L^2 - 25L = 5100

L^2 - 25L - 5100 = 0

This is a quadratic equation. We would solve by applying the method of factorization. The first step is to multiply L^2 with - 5100. It becomes - 5100L^2. We would find two terms such that their sum or difference is - 25L and their product is - 500L^2. The terms are 60L and - 85L. By replacing - 25L with 60L - 85L, we have

L^2 + 60L - 85L - 5100 = 0

We would factorize by grouping. It becomes

L(L + 60) - 85(L + 60) = 0

Since L + 60 is common, it becomes

(L + 60)(L - 85) = 0

L + 60 = 0 or L - 85 = 0

L = - 60 or L = 85

The length cannot be negative. Thus,

L = 85

Substituting L = 85 into Width = L - 25,

Width = 85 - 25

Width = 60

Length = 85

User Dietmar
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