Always True
Part of the Fundamentals section of Coddy's Algebra journey. Lesson 44 of 61.
The opposite can happen too. Take the equation . Distribute the left side, and both sides become . Subtract from both sides:
What is left is a true statement with no in it. A true statement means the original equation is true for every value of . Try , or , and both sides always agree. An equation like this is called an identity, and its solution is all numbers.
When the unknown cancels out, look at the statement that is left. If it is false, the equation has no solution. If it is true, every number is a solution. Both of these are complete answers.
Challenge
MediumSolve . Distribute first, then compare the two sides.
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