Answer
33°
Work Step by Step
We know that the angles of a triangle must add up to 180°. We are given that the angles of this triangle are 57°, 90°, and x°. Therefore, we can sum these up and set the sum equal to 180° to solve for the unknown angle.
$57+90+x=147+x=180$
Subtract 147 from both sides.
$x=33°$
Recall that the square symbol indicates a right angle, which is equal to 90°.