AGHHH HELLP I don't get this at all.

What number should be placed in the box to help complete the division calculation?

Long division setup showing an incomplete calculation. 16 is in the divisor, 3426 is in the dividend, and 2 hundreds and 1 tens is written in the quotient. 3200 is subtracted from 3426 to give 226. An unknown value represented by a box is being subtracted from 226.

Okay so for every triangle has three angles that always add up to 180 degrees. and to tell the difference between whether they are secure, right or obtuse is that acute: has one angle that is less than 90 degrees. right triangle means there is at least one angle that is exactly 90 degrees. and an obtuse angle has an angle that is bigger than 180 degrees. i’ll do #13 as an example: 13. 40 and 50 so if every triangle has 180 degrees 40+50= 90 degrees then180-90= 90 degrees so the third angle is 90 degrees and because this triangle has a 90 degree angle it means it is a right triangle