The perimeter of a rectangle is 42 inches, and the area is 98 square inches. Find the length and width of the rectangle.

Question

2 answers

Answer 1

Perimeter P=2(a+b)=42 , a, b sides of the Rectangle

Area S=a*b=98

Now we have 

 

2(a+b)=42

a*b=98

 

a+b=21

a*b=98

 

from the first equation a=21-b, and plug it into the second

 

(21-b)*b=98

21b-b^2=98

b^2-21b+98=0

 D=21^2-4*98=49

b1=(21+7)/2

b2=(21-7)/2

 

and then you find a ...

 

 

 

a(21-