Mathematics
Math Equations
Quick fact
The equals sign '=' was invented in 1557 by Welsh mathematician Robert Recorde, who said that no two things can be more equal than two parallel lines of the same length.
Why this is interesting
You know that 2 + 3 = 5 is always true. But what if we wrote 2 + x = 5? Suddenly, the simple statement turns into a puzzle: what number makes it true? That's the power of an equation.