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34 votes
34 votes
The area of the rectangle is 45 cm ²

User Bernadetta
by
3.2k points

1 Answer

23 votes
23 votes
(x + 5)(x + 2) = 45

x^2 +7x +10 = 45

x^2 +7x -35 = 0

x = (-7 + sqrt(49 +140))/2

x = 3.374

5.374 * 8.374 = 45.001876 - which is close enough.

Or ??!! ⬇️

Lets say length is L and Breadth is B

So L x B=45 ^2= 2025

L-5=B-2 ( sides of the square are equal)

Or L-B=3

From elementary algebra We know that

(L+B)^2=(L-B)^2+4LB=3^2+4x2025 =9+8100

=8109

So L+B=sqrt(8109)=90 approximately Adding L+B and L-B we get 2L=93 L=46.5or side of square =46.5- 5=41.5 cm approximately
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Wolf Boehrendt
, Diploma (Master) Mathematics & Physics, University of Tübingen (1969)
Answered 1year ago
· Author has 785 answers and 326.8K answer views
User Imolit
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