What is a true sentence in math?

Answer 1

A sentence is made up of two expressions connected by an equal sign or an inequality sign (such as <).

If there's an '=' sign, it's an equation, otherwise it's an inequality.

A sentence with a variable in it is called an open sentence - you need to put a number in for the variable to see whether it is true or false.

If the sentence has no variable in it, then we can decide whether it is true or false.

Examples of a true sentences:

1 + 6 = 7

4 > 2

5 + 17 = 11 times 2 .