If you graph a linear function, you get a line. If you graph a quadratic function, you get something called a parabola. A parabola tends to look like a smile or a frown, depending on the function. Check out this tutorial and learn about parabolas!
Orange Door Meanings. Orange is a colour associated with Mercury, which is the swiftest of the planets. Indeed the planet as the fleet-footed Roman god is symbolic of for reception, communication, perception, commerce, movement, intelligence and flexibility. With these kind of qualities, it might be a good idea to paint your business door orange.
The most welcoming colors for the front doors at the moment are turquoise, blue, red and dark red and all hues of brown from light brown to dark chocolate. So you can never get wrong if you paint your front door in your favorite color and give your house extravagant look. Source. Source.