A math expression is anything where you take one or more numbers and add them, subtract them, multiply, divide, etc etc
For example, 2+3 is a math expression
To make it an algebraic expression, we replace one of the numbers with a variable. Often this is the letter x. So let's say we replace the 2 with x. That would have the expression turn into x+3. What we're saying is "some number plus 3"
Normally 2+3 = 5 which is a true equation. Replace the 2 with x and we have x+3 = 5. So we're saying "some number plus 3 is 5". You can guess and check to find that the "some number" has to be 2
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In summary, the expression example was x+3 and the equation was x+3 = 5
Note: an equation is simply two expressions set equal to each other.
