What is the Difference of mathematical phrase and mathematical sentence?

A mathematical phrase is a combination of numbers, variables, and operations that does not include an equality sign, such as "3x + 5" or "the sum of a and b." In contrast, a mathematical sentence is a complete statement that includes an equality or inequality sign, such as "3x + 5 = 12" or "a + b > 10." Essentially, phrases express relationships or quantities, while sentences assert a specific truth or comparison.