What must NOT be included in an expression? 1. an equals sign

2. at least one variable

3. one or more numbers

4. an operation such as addition

1. an equal sign

Step-by-step explanation:

An expression is a mathematical statement that does not contain an equal sign. It cannot be solved for unless the value of the variable is given.

1. an equals sign

Step-by-step explanation:

expression does NOT have a equal sign but an equation does have an equal sign.

m∠5 + m∠3 = m∠1   is true.

m∠5 + m∠6 = 180 is true

m∠2 +m∠3 = m∠6   is true

m∠2 +m∠3 +m∠5 = 180   is true