Question

I don't get it.... I checked my book for the answers and it shows usless info

Answer 1

that type of corner angle is a 90° angle, so since you know the first half of the 90° angle which is 67.4 all you need to do is subtract

so you get
90 - 67.4 = 22.6

Answer 2

x= 22.6

Explanation:

This little red square means that is a right angle (90 degrees)

x is the complementary of 67.4 (Both add to 90)

90-67.4 = 22.6