Applied Mathematics

Any statement, usually involving multiple objects + Mathematics = This trope

This is when a statement regarding real-world things is expressed as a mathematical equation, usually in the form of x + y = z to quickly tell you what you get when you mix x and y. Also common is writing an elaborate deduction on a blackboard or thought bubbles, but substituting a few terms, including the result, with pictures related to whatever the character is scheming.

Try not to think too hard about the implications of some of these. For example, Quantum Mariah Carey Problem is equal to this trope plus Fridge Logic.

Parallel to E Equals MC Hammer, when used to convey a setting or a character's skills, and may be derivative of Writers Cannot Do Math.

Integral to Troperithmetic. Rebus Bubble is a subset of this.

Anime

 * It's probably closer to Memetic Mutation, but Batman + Humongous Mecha = The Big O
 * By the same token, Death Note + Humongous Mecha = Code Geass.

Literature
"Let legs equal four...."
 * In the Discworld novels (but also referring to the real world, and why time can be lost in bookshops): Libraries are collections of books and books contain knowledge. Knowledge = power = energy = matter = mass. "A good bookshop is a genteel black hole that knows how to read."
 * Camel mathematicians also think in these terms.


 * In A Wrinkle in Time, Mrs. Who uses her skirt and an ant to illustrate her explanation of the tesseract.

Live Action Television

 * In Kenan and Kel, Kenan uses this trope to explain Kel his plan, Kel then tells him he can't add things that aren't numbers.
 * Used in Numb3rs.

Video Games

 * The first few levels of Super Paper Mario feature "joke" equations in the background, made up of random numbers and mathematical symbols combined with famous Mario icons such as the Fire Flower and mushrooms.
 * In Mickey Mania, when you fight the Mad Doctor, there is a nonsensical equation - featuring Pluto - in the background.
 * Alchemy, a series of games for mobile devices including iOS and Android phones and tablets, starts you off with the four classical elements (earth,air,fire,water) and forces you to apply this trope to find all the rest.

Web Comics

 * Xkcd is fond of it.
 * And then there's Indexed.
 * Keychain of Creation brings us this.
 * From Dumbing Of Age: Your mom + Nickel = Prostitute
 * The Adventures of Dr. McNinja has this.
 * Surviving the World

Web Original

 * The title card for The Angry Video Game Nerd video "Chronologically Confused" features the Nerd in front of a board filled with nonsensical equations and formulae, including at points a Triforce and a drawing of Mario.
 * Of particular note is ET=BS.
 * The Rocketboom series, Know Your Meme, has its own brand, called Mememath.
 * The Nostalgia Chick had the below joke about women equaling time and money therefore they're evil at the start of her "Top Eleven Villainesses."

Western Animation
"Candace: Wait! Maybe I should've carried the one instead of dividing by Jeremy's face."
 * Duck Dodgers: Daffy draws a complicated navigation chart to navigate to Planet X, and then Porky suggests they just follow the letters on the planets.
 * The Simpsons, when Homer is an inventor. During a montage, he's shown writing equations on a blackboard. After he's done, the camera moves to shot of the house ? where there's a massive explosion. Cut back to Homer: who examines his equation and crosses out the offending section, a drawing of a stick of dynamite, which he then replaces with something else. This results in another, bigger explosion.
 * Also Homer's brain leads to
 * South Park, in the episode "Simpsons Already Did It": Cartman's explanation for how adding semen to his tank of "Sea People" (brine shrimp) caused them to develop a civilisation: Sea-People + Sea-Men = Sea-Ciety
 * In Pinky and The Brain, the Brain tries to mathematically deduce the reason his plans usually fail. He ends up with a portrait of Pinky. Later, Pinky is made smarter and finds several mistakes in Brain's calculations. Correcting them results in a portrait of Brain.
 * In Jackie Chan Adventures, Jade references combining the levitation talisman and the speed talisman to fly by saying 'levitation+speed=flight.'
 * In the Phineas and Ferb episode "Out to Launch," Phineas and Ferb are trying to get a rocket to launch using a scientific equation (You can see it starting at 3:18 here), and with each new attempt, Phineas modifies one of the terms. After a few false starts, Ferb points out the problem: the equation equals the square root of a bomb. Phineas changes it to a smiley face, and their next launch is successful.
 * 'Tis Tsiolkovsky's equation, the foundation of rocketry!
 * Another episode had Jeremy tell Candace he'd call her soon and Candace decided to calculate out when "soon" was.


 * The Boondocks: Nigga Moment + Nigga Synthesis = COMPLETE DISASTER
 * Codename Kids Next Door: Operation A.R.C.H.I.V.E, which is an Affectionate Parody of The Animatrix, ends with the narrator launching into an erratic rant about fluorescent lights, schools and curfews all being a part of the adult conspiracy to subdue their creators, the children. The rant is accompanied by rapid flashes of increasingly disturbing images, one of which is a chalkboard which says "2+2=Go to Bed".
 * In The Nightmare Before Christmas, Jack puts a number of these "equations" on a blackboard to try and understand Christmas.

Other

 * There's the old joke that goes like this:
 * Getting a girlfriend is the product of time and money. Girlfriend = Time * Money
 * Time = Money, therefore Girlfriend = Money * Money = Money^2
 * Money is the root of all evil, Money = Evil^(1/2)
 * To pick nits, technically the love of money is the root of all evil.
 * Therefore Girlfriend = Evil
 * Counter joke:
 * Boyfriend = Girlfriend * Time * Money
 * Boyfriend = Evil * Money^2
 * Boyfriend = Evil^2
 * And similarly again:
 * Time is Money, Knowledge is Power: T = $, K=P
 * Power is work per unit time: P=W/T so T =W/P
 * Therefore $=W/K, and since lim (W/K) as K increases tends to zero, the More you know the less you make regardless of how hard you work.
 * Tolkien as Calculus
 * As Vladimir Lenin put it, communism is the Soviet power plus electrification of the whole country. Therefore, 1) Soviet power is communism without elecrification, and 2) electrification is communism minus Soviet power. Important note: this joke is political, and was subject to persecution.
 * An advert about not using a cellphone while driving was portrayed as "driving person + cell phone = walking person". That this logically means "walking person - cell phone = driving person".
 * The rapper Canibus had an interesting equation on his 1000 bar opus "Poet Laureate Infinity" that goes: "If A is a success in life, then A must equal X plus Y plus Z no doubt / If work equals X and play equals Y, then Z must be equal to you shutting your mouth."
 * Pretty Sure Einstein said that first.