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Please answer with clear instructions so that i can apply this to other questions.

Please answer with clear instructions so that i can apply this to other questions-example-1
User Denis Shevchenko
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1 Answer

15 votes
15 votes

Answer:

length = 50 cm

Explanation:

let width be w then length = w + 10

area = w(w + 10) = 2000 , that is

w² + 10w = 2000 ( subtract 2000 from both sides )

w² + 10w - 2000 = 0 ← in standard form

Consider the factors of the constant term (- 2000 ) which sum to give the coefficient of the w- term ( + 10)

the factors are + 50 and - 40 , since

50 × - 40 = - 2000 and sum = 50 - 40 = + 10

(w + 50)(w - 40) = 0 ← in factored form

equate each factor to zero and solve for w

w + 50 = 0 ⇒ w = - 50

w - 40 = 0 ⇒ w = 40

Since w > 0 then w = 40 and

length = w + 10 = 40 + 10 = 50 cm

User Hellter
by
2.4k points
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