STEP 1: find side $ x $

To find side $ x $ use formula:

$$ x = \frac{ a - b } { 2 } $$

After substituting $a = 136\, \text{mm}$ and $b = 60\, \text{mm}$ we have:

$$ x = \frac{ 136\, \text{mm} - 60\, \text{mm} } { 2 } $$ $$ x = \frac{ 76\, \text{mm} } { 2 } $$ $$ x = 38\, \text{mm} $$

STEP 2: find height $ h $

To find height $ h $ use Pythagorean Theorem:

$$ h^2 + x^2 = c^2 $$

After substituting $x = 38\, \text{mm}$ and $c = 125\, \text{mm}$ we have:

$$ h ^ {\,2} + \left( 38\, \text{mm} \right)^{2} = \left( 125\, \text{mm} \right)^{2} $$ $$ h ^ {\,2} = \left( 125\, \text{mm} \right)^{2} - \left( 38\, \text{mm} \right)^{2} $$ $$ h ^ {\,2} = 15625\, \text{mm}^2 - 1444\, \text{mm}^2 $$ $$ h ^ {\,2} = 14181\, \text{mm}^2 $$ $$ h = \sqrt{ 14181\, \text{mm}^2 } $$$$ h = \sqrt{ 14181 }\, \text{mm} $$

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