Step by step please !

Step-by-step explanation:

Since the sum of all interior angles of a triangle is 180 degrees, we are able to derive the answer of what x (m<1 in this case) measures.

For example, in number 1, you can do

m<1 = 180 - 94 - 45

For the 2nd one, the tick marks show that the highlighted angles measure the same.

So, it would be (180-58)/2 = m<1

Finally, for the third one, there is a right angle, meaning that it measures 90 degrees

Therefore, 180-90-77 = m<1