Question

The sum of the measures of the angles in a quadrilateral is (blank) degrees??

Answer 1

A square is also a quadrilateral. Do you know the angles of a square?

Answer 2

eerrrr, I can't really say the answer, but it's twice the sum of angles in a triangle.

Answer 3

@hayley_baby19 Can you try?

Answer 4

what ash2326 said is the way to go.
since all quadrilateral verify the claim, you can choose one type of quadr. for which this sum is easy to compute:

find "a", multiply by 4, and you get that number you're looking for.