Answer:
A = 192 cm²
Step-by-step explanation:
Given that,
The length of the diagonal of a rectangle is 20 cm.
The difference between its length and its width is 4 cm.
Let the length is l and width is b.
ATQ,
l-b = 4 ...(1)
Let x is the diagonal of the rectangle such that,
[tex]x^2=l^2+b^2[/tex]
or
[tex]20^2=l^2+b^2\\\\l^2+b^2=400[/tex] ....(2)
Now we need to solve equation (1) and (2).
Squaring equation (1) : [tex]l^2+b^2-2lb=16[/tex]
Put equation (2) in above equation.
[tex]400-2lb=16\\\\400-16=2lb\\\\2lb=384\\\\lb=192[/tex]
Since, the area of the rectangle, A = lb
A = 192 cm²