Find the corners of a rectangular trapezoid if the large angle is 160 °.

The condition says that we are given a rectangular trapezoid, and it is also known that one of its angles is 160 °.

Let’s first of all remember what the sum of the angles of the quadrilateral is equal to.

The angles of a quadrilateral add up to 360 °.

A rectangular trapezoid has two right angles.

Let’s denote the unknown angle of a rectangular trapezoid with the variable x.

x + 90 ° + 90 ° + 160 ° = 360 °;

Now let’s solve the resulting linear equation in one variable:

x = 360 – 90 – 90 – 160;

x = 20 ° is the fourth corner of a rectangular trapezoid.