It is D.
you must multiply the second equation by 3, so that the +3y in the first equation can cancel out the (now) -3y in the second equation.
Answer:
The answer is 7.4
Step-by-step explanation: I don’t really know a better way to tell you the explanation than just tell you the answer
Answer:
900
Step-by-step explanation:
The sum of the interior angles of a polygon with n sides is given by the formula:

The polygon given has 7 sides. Substitute 7 for n. Thus:

The sum of the interior angles is 900 degrees.