Question

What is the length and width of a rectangle if Area is 20 and perimeter is 20

Answer 1

Answer: a=5+√5

b=5-√5

Step-by-step explanation:

a=?

b=?

P=20

A=20

P=a*b=20

A=a+b=20

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ab=20

a+b=10

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a=10-b

(10-b)b=20

-b²+10b-20=0

b=-10±√100-80/-2

b=-10±√20/-2

b=-10±2√5/-2

b=-10-2√5/-2=5+√55

b=5-√5

a+b=10

a+5-√5=10

a=5+√5

a+5+√5=10

a=5-√5