Notice that angle of measure x degrees PLUS the angle of measure 41 degrees add up to give a RIGHT angle (90 degrees) as marked with the identifiable little square by the vertex.
Then we can write the equation:
x + 41 = 90
and solve for x by subtracting 41 from both sides
x = 90 - 41 = 49 degrees.
In the case of the second problem, we are seeing two "supplementary angles" whose addition should give 180 degrees (a straight line)
So we write the equation:
x + 133 = 180
and solve for x by subtracting 133 from both sides:
x = 180 - 133 = 47 degrees.
