STEP 1: find side $ a $
To find side $ a $ use formula:
After substituting $ B = 16 $ we have:
$$ B = a^2 $$ $$ a^2 = 16 $$ $$ a = \sqrt{ 16 } $$ $$ a = 4 $$STEP 2: find lateral surface $ L $
To find lateral surface $ L $ use formula:
$$ L = 2 \cdot a \cdot s $$After substituting $ a = 4 $ and $ s = 8 $ we have:
$$ L = 8 \cdot 8 $$$$ L = 64 $$STEP 3: find total surface $ A $
To find total surface $ A $ use formula:
$$ A = B + L $$After substituting $ B = 16 $ and $ L = 64 $ we have:
$$ A = 16 + 64 $$ $$ A = 16 + 64 $$ $$ A = 80 $$