Question
Find the side $ a $ of a rectangle if side $b = 5\, \text{cm}$ and perimeter $P = 60\, \text{cm}$.
Answer
$25\, \text{cm}$
Explanation
To find side $ a $ use formula:
$$ P = 2 a + 2 b $$After substituting $P = 60\, \text{cm}$ and $b = 5\, \text{cm}$ we have:
$$ 60\, \text{cm} = 2 a + 2 \cdot 5\, \text{cm} $$ $$ 60\, \text{cm} = 2 a + 10\, \text{cm} $$ $$ 2 a = 60\, \text{cm} - 10\, \text{cm} $$ $$ 2 a = 50\, \text{cm} $$ $$ a = \dfrac{ 50\, \text{cm} }{ 2 } $$ $$ a = 25\, \text{cm} $$This page was created using
Rectangle Calculator