thanks, Krishnamurthy for the translation.

a = 2b

(a + 40)(b + 6) = 2ab

2b^2 - 52b - 240 = 0

rule b'

[26 ± √(26^2 + 480)] / 2

b = 30m and a = 60m

p = 2(a + b )

p = 2 x 90 = 180m

What is the perimeter of a rectangle if its base is twice the width.

If the length increases 40 m and the width 6 m, the area is doubled?

is urgent