Question 935304
Call the sides {{{ a }}} and {{{ b }}}, where
{{{ a/b = 16/9 }}}
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By the pythagorean theorem:
{{{ 70^2 = a^2 + b^2 }}}
{{{ 4900 = a^2 + b^2 }}}
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{{{ a/b = 16/9 }}}
Multiply both sides by {{{ 9b }}}
{{{ 9a = 16b }}}
{{{ a = ( 16/9 )*b }}}
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By substitution:
{{{ 4900 = ( 16^2 / 9^2 )*b^2  + b^2 }}}
{{{ 4900 = ( 256 / 81 )*b^2 + ( 81/81 )*b^2 }}}
{{{ 4900 = ( 337/81 )*b^2 }}}
{{{ b^2 = ( 81/337 )*4900 }}}
{{{ b = ( 9*70 ) / sqrt(337)  }}} 
{{{ b = 630 / 18.358 }}}
{{{ b = 34.32 }}}
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{{{ a/b = 16/9 }}}
{{{ a = ( 16/9 )*b }}}
{{{ b = ( 16/9 )*34.32 }}}
{{{ b = 61.01 }}}
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check answers:
{{{ 4900 = a^2 + b^2 }}}
{{{ 4900 = 61.01^2 + 34.32^2 }}}
{{{ 4900 = 3722.63 + 1177.86 }}}
{{{ 4900 = 4900.49 }}}
Error due to rounding off, I think