STEP 1: find diagonal $ d2 $
To find diagonal $ d2 $ use formula:
$$ d_1^2 + d_2^2 = 4 \cdot a^2 $$After substituting $d_1 = 35\, \text{cm}$ and $a = 20.16\, \text{cm}$ we have:
$$ \left( 35\, \text{cm} \right)^{2} + d_2^2 = 4 \cdot \left( 20.16\, \text{cm} \right)^{2} $$ $$ 1225\, \text{cm}^2 + d_2^2 = 1625.7024\, \text{cm}^2 $$ $$ d_2^2 = 1625.7024\, \text{cm}^2 - 1225\, \text{cm}^2 $$ $$ d_2^2 = 400.7024\, \text{cm}^2 $$ $$ d_2 = \sqrt{ 400.7024\, \text{cm}^2 } $$$$ d_2 = 20.0176\, \text{cm} $$STEP 2: find area $ A $
To find area $ A $ use formula:
$$ A = \dfrac{ d_1 \cdot d_2 }{ 2 } $$After substituting $d_1 = 35\, \text{cm}$ and $d_2 = 20.0176\, \text{cm}$ we have:
$$ A = \dfrac{ 35\, \text{cm} \cdot 20.0176\, \text{cm} }{ 2 }$$$$ A = \dfrac{ 700.6143\, \text{cm}^2 }{ 2 } $$$$ A = 350.3072\, \text{cm}^2 $$STEP 3: find height $ h $
To find height $ h $ use formula:
$$ A = a \cdot h $$After substituting $A = 350.3072\, \text{cm}^2$ and $a = 20.16\, \text{cm}$ we have:
$$ 350.3072\, \text{cm}^2 = 20.16\, \text{cm} \cdot h $$$$ h = \dfrac{ 350.3072\, \text{cm}^2 }{ 20.16\, \text{cm} } $$$$ h = 17.3763\, \text{cm} $$