I don’t understand how to find x. Please explain!

X=60

Step-by-step explanation:

The little square near 150 means- that angle is right, i.e 90.

Like you can see, x, 30 and 90 are on the the same straight line, so the some of them is 180.

30+90+x=180

120+x=180

x=60

x = 60 degrees.

Step-by-step explanation:

The angle marked with a square indicates that it is 90 degrees. So the 'square' angle to the left of it is also 90 degrees, as they are on the same straight line, so their sum is 180 degrees.

Therefore  x + 30 = 90

x = 60 degrees.

{3 + i, 3 - i, 3, -1}

step-by-step explanation:

1/800 is the right answer