Marta said 50+ 1/2m=120 is an equation, while maribel argued that it is an expression. determine who is correct and explain why.

Marta is correct. This is an equation. The statement includes an equal sign. Equations include an equal sign, expressions do not include an equal sign.

(6n) Is the arc measure of BAC

Step-by-step explanation:

The arc measure is  the piece not included in the arc, The arc goes counterclockwise starting at the b radius all the way to the c radius. The arc includes (7n+12) and (13n-16) inside of it. (6n) is the chunk left out.