a rectangle has a perimeter of 60 cm let X represent the length of one side of the rectangle which of the following functions models the area A(x) of the rectangle?

A. A(x) = x^2 + 30x
B. A(x) = 30x - x^2
C. A(x) = x^2 + 60x
D. A(x) = 60x - x^2

Respuesta :

Answer:

B.

Step-by-step explanation:

P(x)= 2( x+y)  //Rectangle perimeter              =>   A(x)= xy         //Rectangle area

60 = 2(x+y)                                                                   =x(30-x)  //Substituting y            

60/2= [2(x+y)]/2                                                            =30x - x²

  30= x+y

B. Is the answer I hope that helps