An equation, which contains the square of the unknown (variable) quantity, but no higher power, is called a

• Linear equation

• Quadratic equation

• Completing square

• Cubic equation

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Quadratic equation

A quadratic equation is a type of equation that contains the square of the unknown quantity (or variable), but no higher powers. In other words, it is an equation that can be written in the form:

ax² + bx + c = 0

where "x" is the unknown variable, "a", "b", and "c" are coefficients (numbers), and "^2" denotes that the variable is being squared. This equation is known as the standard form of a quadratic equation.