The second tool concerns multiplication and division. Here there is a condition that must never be forgotten: the factor must be different from zero.
Property — Second principle of equivalence
Multiplying or dividing both sides by the same quantity different from zero, the equation obtained is equivalent to the original one.
Warning
The condition “different from zero” is essential: multiplying both sides by would turn any equation into the equality , losing all information about the solutions.
Links
Topics: First-degree equations
Concepts: Equation · Principle of equivalence
Skills: Solving equations