One true purpose for which you could use a quadratic equation could be to figure the maximum use of crop planting in a field once you have the true area of the field figured. Quadratic equations can also be used to figure the area or the volume or the capacity of any unusually shaped object.
By using the quadratic equation formula or by completing the square
Without an equality sign the given quadratic expression can't be classed as an equation but knowing how to use the quadratic equation formula would be helpful when given such problems.
The Quadratic Equation is useful because you can't factorevery equation, so you use the quadratic equation. Even though it doesn't seem fun it is still useful.
To find the roots (solutions) of a quadratic equation.
I suggest you use the quadratic formula.
Simply learn and use the quadratic equation formula.
By using the quadratic equation formula or by completing the square
you use the quadratic formula in math when the quadratic equation you are solving cannot be factored.
By knowing how to use the quadratic equation formula.
Because it's part of the quadratic equation formula in finding the roots of a quadratic equation.
Without an equality sign the given quadratic expression can't be classed as an equation but knowing how to use the quadratic equation formula would be helpful when given such problems.
The Quadratic Equation is useful because you can't factorevery equation, so you use the quadratic equation. Even though it doesn't seem fun it is still useful.
To find the roots (solutions) of a quadratic equation.
You should always use the vertex and at least two points to graph each quadratic equation. A good choice for two points are the intercepts of the quadratic equation.
I suggest you use the quadratic formula.
Probably never.
The quadratic formula can be used to find the solutions of a quadratic equation - not a linear or cubic, or non-polynomial equation. The quadratic formula will always provide the solutions to a quadratic equation - whether the solutions are rational, real or complex numbers.