If it doesn't have an equal sign, then it's not an equation.
Never. By definition, the two sides of an equation are equal.
Equality. If they are ALWAYS equal then the equation is an identity.
A formula does not have an equal sign. An equation has an equal sign. That's why it is an equation.
An expression has no equal sign whereas an equation does have an equal sign
An equation that states that two ratios are equal is a proportion.
An equation has two sides, and each of these sides is equal to the other.
That is the definition of the term "equation".
An equation must have an equal (=) sign and both side are the same, that is, equal to each other.
An equation has an equal sign, a expression does not.
Equation: x+3=3+x (notice the equal sign: equal; equation)Expression: x+3 (notice no equal sign)