The midline of the trapezoid is 29 and the smaller base is 21. Find the larger rigging of the trapezoid.

A trapezoid is a quadrilateral in which one pair of opposite sides is parallel, and the sides are not equal to each other.
The midline of a trapezoid is a line segment connecting the midpoints of the sides of the trapezoid. It is parallel to the bases, and its length is equal to half the sum of the bases:
m = (a + b) / 2;
m is the middle line of the trapezoid NK;
a – smaller base of the BC trapezoid;
b – greater base of blood pressure.
In this way:
NC = (BC + AD) / 2;
(BC + AD) = 2 ∙ NK;
AD = 2 ∙ NK – BC;
AD = 2 ∙ 29 – 21 = 58 – 21 = 37 cm.
Answer: the length of the larger base is 37 cm.