Simplify 13 +4(9-7) and solve

21 hope this helps

Step-by-step explanation:

Hi there!

The missing angle is 23 degrees.

Remember every triangle has 180 degrees no matter what type. So you add 75 and 82 and subtract it from 180 giving you 23.

The first name is acute and the last name is scalene.

A acute triangle is when all angles are less than 90 and an obtuse triangle is when there is 1 obtuse angle and 2 acute angles.

Hope this helps !