MathPlus's definitions

Why an X

When it is more effective to use a general letter x rather than a concrete numeral to represent a number, whose value constantly varies—an economic way to convey the idea of a variable in an equation or a mathematical sentence.

Why an X, and not an A, B, or C is because the letters x, y, and z have traditionally been used to stand for unknowns, while the letters a, b, and c for constants.

by MathPlus November 18, 2018

Wayang Math

When someone shows off the success of their exam-smart or pseudo-talented kids or tutees in school or olympiad math, by posting photos of their grades, awards, medals, or certificates on social media, dreaming for a googol likes in return—wayang is a Malay word that mockingly describes someone as being “fake” in the sense that they are putting up an act in front of others.

Guesstimate how many wayang math postings appear on Facebook and Instagram every year by oft-kiasu or egocentric parents to hint to their social circles of their “supernatural” parenting or tutoring skills.

by MathPlus November 13, 2021

The Model Method

Also known as “Singapore model method,” “bar model method,” or “bar modeling.” A problem-solving visualization strategy whereby the problem solver makes use of rectangles or bars to draw a model diagram to represent how the known and unknown quantities in a given problem situation are related, using a part-whole or comparison model.

Using the model method to solve a word problem involving fraction, ratio, or percentage allows the mind’s eye to better grasp the problem situation by making tacit knowledge more explicit or visible—it’s like a “look-see” proof to a problem for kids.

by MathPlus October 5, 2021

Mr. Right

A nickname given to a math teacher who always reminds his students not to assume that an angle in a geometric figure is ninety degrees, although it may deceptively look like it is a right angle.

Students of Mr. Wright call him “Mr. Right Wright” or “Mr. Right Squared,” because he won’t give them any marks if they assume without proof that a triangle is a right triangle.

by MathPlus January 18, 2019