The bases of the rectangular trapezoid are 14 cm and 17 cm, one of the corners is 60⁰.

The bases of the rectangular trapezoid are 14 cm and 17 cm, one of the corners is 60⁰. Find the large side of the trapezoid.

Select a right-angled triangle formed by the height of the trapezoid, the lateral side, and an angle equal to 60⁰. From this triangle, you can find the side of the trapezoid, which is the hypotenuse of the resulting triangle.

The leg of the triangle is the difference between the bases – larger and smaller.
The leg of the triangle is (17 – 14) = 3 (cm).
Hypotenuse = lateral side = leg / sin (60⁰ – 30⁰) = 3 / sin 30⁰ = 3 / (1/2) = 6 (cm).

The leg equal to 3 cm is opposite the angle equal to (60 ⁰- 30 ⁰) = 30.