Question
Find the short base $ b $ of a trapezoid if long base $a = 21\, \text{cm}$ and median $m = 17\, \text{cm}$.
Answer
$55\, \text{cm}$
Explanation
To find short base $ b $ use formula:
$$ m = \frac{ a + b } { 2 } $$After substituting $m = 17\, \text{cm}$ and $a = 21\, \text{cm}$ we have:
$$ 17\, \text{cm} = \frac{ 21\, \text{cm} + b } { 2 } $$ $$ 17\, \text{cm} \cdot 2 = 21\, \text{cm} + b $$ $$ 21\, \text{cm} + b = 34\, \text{cm} $$ $$ b = 21\, \text{cm} + 34\, \text{cm} $$ $$ b = 55\, \text{cm} $$This page was created using
Trapezoid Calculator