Draw two perpendicular lines, label the angles A, B, C, D, describe their relationship, and solve for x if one angle is 2x+10 degrees.

Draw a straight horizontal line. Then, draw a straight vertical line that crosses the horizontal line exactly at its midpoint. The point where these two lines intersect is point O.

Starting from the top-right quadrant and moving counter-clockwise, label the angles.

• The angle in the top-right quadrant is A.
• The angle in the top-left quadrant is B.
• The angle in the bottom-left quadrant is C.
• The angle in the bottom-right quadrant is D.

When two lines are perpendicular, they intersect to form four right angles.
Therefore, all four angles formed at the intersection are equal to $90^\circ$.

Additionally, vertically opposite angles are equal ($\angle A = \angle C$ and $\angle B = \angle D$), and adjacent angles on a straight line are supplementary (e.g., $\angle A + \angle B = 180^\circ$).