STEP 1: find angle $ \beta $
To find angle $ \beta $ use formula:
$$ \alpha + \beta = 90^o $$After substituting $ \alpha = 37^o $ we have:
$$ 37^o + \beta = 90^o $$ $$ \beta = 90^o - 37^o $$ $$ \beta = 53^o $$STEP 2: find height $ h $
To find height $ h $ use formula:
$$ \sin \left( \alpha \right) = \dfrac{ h }{ a } $$After substituting $\alpha = 37^o$ and $a = 5\, \text{cm}$ we have:
$$ \sin( 37^o ) = \dfrac{ h }{ 5 } $$ $$ 0.6018 = \dfrac{ h }{ 5 } $$$$ h = 0.6018 \cdot 5 $$$$ h = 3.0091 $$STEP 3: find diagonal $ d2 $
To find diagonal $ d2 $ use formula:
$$ \sin \left( \frac{ \beta }{ 2 } \right) = \dfrac{ h }{ d_2 } $$After substituting $\beta = 53^o$ and $h = 3.0091\, \text{cm}$ we have:
$$ \sin \left( \frac{ 53^o }{ 2 } \right) = \dfrac{ h }{ d_2 } $$ $$ \sin( \frac{ 53 }{ 2 }^o ) = \dfrac{ 3.0091\, \text{cm} }{ d_2 } $$ $$ 0.4462 = \dfrac{ 3.0091\, \text{cm} }{ d_2 } $$ $$ d_2 = \dfrac{ 3.0091\, \text{cm} }{ 0.4462 } $$ $$ d_2 = 6.7438\, \text{cm} $$