1 #include "Rectangle.h" 2 Rectangle(double width,double height)3Rectangle::Rectangle(double width, double height) 4 : width_(width), height_(height) {} 5 area() const6double Rectangle::area() const { 7 return width_ * height_; 8 } 9 perimeter() const10double Rectangle::perimeter() const { 11 return 2 * (width_ + height_); 12 }