Respuesta :

Answer:

P=4x+20

A=x^2+10x+21

Step-by-step explanation:

Perimeter=2(x+7)+2(x+3)

2x+14+2x+6

4x+20

Area=(x+7)(x+3)

x^2+10x+21

l = (x + 3)

b = (x + 7)

Area:

= I x b

= (x + 3)(x + 7)

= x(x + 7) + 3(x + 7)

= x² + 7x + 3x + 21

= x² + 10x + 21

Perimeter:

= 2(l + b)

= 2((x + 3) + (x + 7)) = 2(2x + 10)

= 2(x + 3 + x + 7)

= 4x + 20