Question 720371
{{{ 9^( 2x + 3 ) = 2187 }}}
{{{ 9^( 2x + 3 ) = 3^7 }}}
{{{ (3^2)^( 2x + 3 ) = 3^7 }}}
{{{ 3^( 2*( 2x + 3 ) ) = 3^7 }}}
{{{ 3^( 4x + 6 ) = 3^7 }}}
The exponents must be the same on both sides
{{{ 4x + 6 = 7 }}}
{{{ 4x = 1 }}}
{{{ x = 1/4 }}}
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check:
{{{ 9^( 2x + 3 ) = 2187 }}}
{{{ 9^( 2*(1/4) + 3 ) = 2187 }}}
{{{ 9^( 1/2 + 3 ) = 2187 }}}
{{{ 9^( 7/2 ) = 2187 }}}
{{{ (9^(1/2))^7 = 2187 }}}
{{{ 3^7 = 2187 }}}
{{{ 3^7 = 3^7 }}}
OK