Respuesta :

Answer:

A = 9x² + 12x

Step-by-step explanation:

The area (A) of the rectangle is calculated as

A = height × width

  = 3(3x² + 4x) ← distribute parenthesis by 3

   = 9x² + 12x

Answer:

For the blue one:

A1=length*breadth

   =3*3x^2

   =9x^2

For pink:

A2=length*breadth

    =3*4x

    =12x

So the total area is:

A=A1+A2

  =9x^2+12x